I know absolutely nothing about computers, but if your problem is that your old machine isn't compatible with a new computer, why don't you just buy an old computer on Ebay?
Micro$oft end of support for Win7 eminent.
Handy to have internet in the shop for looking up specs, constants, formulas and whatnot. No room or patience for 2 machines out there.
I have piles of old machines, win7 is soon not internetable
aaaaaaaaaaaaaaaaaaaaaaand, the parallel port driver sends Win10 into a boot loop...fml
But why do you need support if you are just going to run a CNC machine? Or am I missing something?