CNC Controller board less than $495 ?

I had a catastrophic computer burnout that also blew up a chip on my MaxNC15 CL controller board.  I'm told the cheapest route is replacement at $495.  I'm looking for other solutions.  Ideal would be a Raspberry Pi solution since it costs only $35 and has probably enough pins to run all axes and if not another $35 for each axis would be way cheaper.  

But I know very little about what stepper motors require for signals and the position sensors and the MaxNC control software for Win98.  Since it's now toast I'm also thinking of giving up than trying to scrimp and save another $500 - but it's so nice for drilling holes and even though it needs TLC it can do some mill jobs a lot cheaper than the nearest CNC shop.

Thanks.