What toys are you wanting to make?
I make all my own toys and use natural materials like wood, leaves, twigs and nuts. I buy sisal rope from a warehouse in Sydney (not an option for you, I know, but surely there'll be lots of ropemakers in Brussels?)
I use two-inch sisal for my main swings (I just allow two big loops of rope to droop down through the roof of the cage, securing it at either end with strong twine).
I use one-inch sisal for perches and boings. For perches, you just tie a fat knot at one end, stretch the rope tightly across the cage and tie another knot at the other end. If you want, you can learn to tie eye-splices from YouTube. They're a bit neater than common knots, but take a bit of mucking around to tie them tightly and neatly.
For boings, you use eight-gauge fencing wire (get it from a feed merchant, or ask a local farmer for a bit - you only need one or two metres). Twist the wire into a loose spiral and then bury the wire in one end, securing it tightly either with a wire wrapping, a cable tie (which you will later cover) or some strong twine. By gently untwisting the rope in sections, it's easy enough to wind it around the wire, covering it completely. Secure at the opposite end as well. If you need to, wrap the end with either strong wire or twine and cover all pointy bits for birdie's safety. Add a hook (can either bend a loop into the top of the wire or add on a carabiner). You can hang a toy from the bottom or leave a long tail of loose rope for birdie to unravel. If you do this, watch him very carefully because some birds have a genius for getting knotted up in unravelled rope!
I use half-inch sisal to make cargo nets. Somewhere in our DIY forum, I've posted instructions for making such a net with large wooden beads. If you can get beads, you can either tie a simple overhand knot or make your own 'beads' by cutting circles out of untreated pallet timber with a hole saw and drilling a good-sized hole in those with a large drill bit.
Pallet timber is *excellent* for large parrots to chew on! Only ever use the untreated stuff (I don't know about elsewhere, but here in Oz it's made out of 'cypress pine' and quite safe). I cut large and small holes out of the slats with a hole-saw and use the resulting 'biscuits' to make toys. The remaining bits of the slat are put on top of the cages and the birds have a great old time chewing them into matchwood from below. Or, sometimes, I'll screw a couple of metal cuphooks into the 'holey' slat and hang it inside the cage for the birds to chew. Either way, they'll have it in splinters over one or two days.
I'm always on the lookout for all kinds of chewables for my birds. I buy baby toys from second hand stores. The BEST toys are the ones that hold a battery - DO make sure it's bird-proof - and play a voice or sound when you (or the bird) press a button. My Madge adores these toys and has several. Pram toys are good because they're usually pretty durable and don't break when bitten. Various kinds of teething toys are also good, as are plastic balls and rattles with a hard bead inside. Be very careful of anything with exposed metal (or even unexposed metal, including bells, that your bird might winkle out. We've had more than one member lose a bird to metal poisoning through the destruction and ingestion of a small bell!
My corella, Rosetta, absolutely *loves* colourful plastic bangles. She has several of these and enjoys wearing them around her neck. (She's such a supermodel!) I get these from op-shops too, always making sure there are no removable parts that could make a choking or metal hazard.
Other bits and pieces I use are cardboards of all kinds (especially the hollow tubes used by haberdashers to roll fabric on) and many kinds of plastics (be careful not to use the softer plastics that can be nibbled into small beads and, perhaps, swallowed). I use large milk containers to fill with shredded paper and small treats - the birds love ferretting their way into these and finding nuts and bits of seed inside.
I bought some six-inch-long stainless steel bolts with two hex nuts and a single wingnut on each. I drilled holes in a cardboard fabric tube and poked the bolts through, securing them with hex nuts inside. About two inches of each bolt sticks out and I put the wingnuts on those. The birds have a lovely time winding the wingnuts around and, eventually, getting them off. No one has yet worked out how to free the bolts from the tubes, they're still trying!
PVC tubing (I use one-inch wide) makes a wonderful playgym when you make up shapes using elbows, cross-pieces and three-ways! Mine is wound with vet tape for stability and that gets grotty over time, so I have to renew it. But it's cheap and the birds love their gym! Ours has a spiral staircase, a huge boing, a three-foot ladder, two swings and a cargo net hanging from it. My poor Dommie (may he RIP) loved it.
The only specialist things I really buy are coloured wooden beads when they're cheap and the occasional drilled wooden perch to affix on the outsides of my cages. Oh, and stainless steel curb chain from the local hardware shop. You can buy good quality plastic chain from crowd-control businesses. It's incredibly cheaper than buying it from a bird-supplies shop (as is everything).
The only thing I wish I could buy but can't seem to find is the plastic end-caps you see on commercially made boings (the ones with a screw top and a split bolt inside). I have a feeling I'll find something just as good in the hardware shop if I look for long enough...
Oh Lord! Sorry for the massive slab of text! I'll leave it in case there's anything useful to you, but yeah: sorry!
