How to convert variable speed brushed DC motor on old lathe

[paulus.v]

Hello all, I want to get a lathe which is fitted with a 10 or 13.5 kW brushed dc motor. The old electronics are not working any more.

I want to find out the best and cost effective way to have the lathe spinning..

1. Should I try, if possible, to build new electronics with the old thyristors?
2. Are there any cheap inverters for the motor?
3. Should I change the motor with a smaller induction motor + VFD and eventually some belt reduction or gears?

The lathe is huge for my needs, I will use it only occasionally and probably never for large parts. I think that a 3kW motor will be enough.

The lathe model is TOS SV 18 RD. The description of the model with pictures is in the attachment.

Thanks