Excellent buy Chaz.!!

If you can fix the PC/OS then it would be worth either replacing the Transformers or buying 415V converter and keeping original.

If you replace the Controller for Mach3 system then you will need analog controller as the servos are analog not Step & direction. Also if using the IP-A then you'll need to check the Servo's have differential encoders on them and Not single ended type. If so you'll have to replace them if possible or get some sort of line converter setup.!

Change transformer for drives etc and Small 0.75Kw VFD will sort the collant pump.

That wiring diagram is going to be priceless but you've still got plenty of head scratching coming your way. Lol