I am glad to hear you got it fixed so easily, most the shafts I get in the shop have the keyway so wore out that a custom key is not an option, but I have done several over the years.
The controller that was on my Vyteck is a 1995 ( as far as I know ) MCY3 , driver boards and a MCY3 PSU Rev. 2 , the boards also have the word MISOMEX printed on them. I still need to finish the wiring on my Vytec, but have ran it with the controls,, it also has a 3 HP Perske spindle.
I also have another router I built with DMM tech. servos and boards running Mach 3 that runs great, I use a Boshe router on it. It has Thompson rails and muli-lead ball screws, it has a 28" x 48" surface area, I did construct the machine so that if I wanted to I could have 28" under the Z axis by raising or lowering the bed, the z axis has 8" travel if I am not mistaken.
Another project I have is a 5 x 10 digital tool router with 2 spindles, 1 is a Perske and the other is just a spindle set up with a drill chuck. I have the original Aneheim controller boards with it and hope to interface Mach 3 directly to the Aneheim driver boards. When I get it done I will have to sell it as I don't have the room for it.
I hadn't thought about contacting Vyteck about the belts, I just figured the machine was so old. When I did contact them they didn't have anyone there that seemed to know anything about the controller or boards.
Anyways , glad you got your machine up and running