1/ steering wheel and boss ,non standard -3 spoke/gti or simillar
2/ front dics conversion kit
3/ 12v coil
4/ seat belts (inertia type 3 point ) 2 of
5/ window winders -not standard
6/ wiper arms 2 of
out of your list, I have a used 12V coil for you
seat belts I'd be getting from a breaker's yard. Get the rear belts from a Polo or something along with the individual receivers for the front belts (avoid receivers where both latches come off one point, you need two separate ones, preferably ones on a stiff stalk as opposed to the floppy "belt" arrangement you see on rear seatbelts. If you go looking at front seat belts from modern cars watch out for the pre-tensioner. It's basically an explosive ram and while some of them have a little key that you can plug into them to make them safe, some don't. I'm not sure how much force it takes to set them off but I'd rather not be around to find out, they could take the head off you, they're that powerful... Rear belts on run-of-the-mill cars don't have them (as far as I've seen) so are a safer option for DIY removal.
look up street style & power for blingy window winders or scour the yards for screw-secured ones.
the wiper arms I have are manky, Martin Murray will have them, from memory they're not that expensive.