Oakland, CA
Last time I checked, the P-Roc only works on WPC, WPC-95, Stern Whitestar, Stern SAM and System 11 (if you build the custom daughterboard). I don't think it will interface with the DataEast/Sega driver board. Gerry can confirm if you PM him.
As far as what you should drive it with, I think a cheap PC is ideal. It doesn't have to be very fast. I just setup a dropbox account on mine so I can automatically sync data between the computer I am developing on and the computer in the machine.
Yes there are ways of making a Raspberry Pi work, but I think the quick iteration on a PC would be ideal.
