If you look on
www.startekinfo.com you get easy and free access to the W201 FSM - there's a PDF there that lists the special tools for the W201 differential rebuild.
I've recently looked up the cost of the pushing part used to remove the smallest pinion bearing cup and it was about 130 euros including tax - that was just the push part (looks a bit like a disc) not the rest of the gucci press and all that jazz...
...ummm good luck with the second mortgage!
If you get stuck for the 722.3/4/5 special tools I can probably help - but not today 'cos I'm a bit busy.