Err, I'd like to say "MAME that sucker!" but I don't know .... if you scrapped the monitor (which I'm assuming is not working), and got rid of the PCB, you'd be left with a control panel and a box, so you'd be able to start from there. At least you'd have the artwork and marquee already in place.
You might be able to re-wire the controls to an encoder to interface with a PC, for MAME purposes ...