First off, based on the building skills you have shown so far, I think you could rewind the motor and get it to function. Your winding may not be as dense as the original. Also, many (maybe almost all) commercial windings are infused with a "varnish". Getting it rewound professionally in the US would probably be cost prohibitive -- I once checked into that cost for a fractional hp British motor, and it was far cheaper to buy a new one and make it fit.
You don't mention the model number of your Proxxon. I have a MicroMark table saw that is like this and have used it to cut PCB's:
With a carbide blade, it works but is not pleasant to use. I do not like being bombarded with little chips of flying copper and PCB. Also, it is quite difficult to get a truly square cut. The PCB will tend to walk on you just a little bit. I currently use a cheap ($25) tile cutter from HomeDepot.
If size is critical, I use a disk sander for that final shape. Cutouts are hard to make either way. There are ways to do that, but that discussion would be way OT.
My recommendations:
1) Fix the saw, but reconsider using it for PCB's.
2) I would try to find a replacement motor for the saw and make it fit, rather than rewind the original motor.
3) Use some sort of shear for the PCB's.
4) For light touch up using hand tools, PermaGrit sanders work. For my disk sander, I just use quality sandpaper.
Finally, I have also used a power scroll saw with a metal cutting blade for PCB's. That is much more pleasant than the circular saw to use.
John