Interested in getting the one you have repaired/restored (probably a day or two turnaround)? I also make an adapter to convert a Joust/Robotron ROM board to Bubbles. I have to look to see if I have a ROM board that doesn't have a matching MPU.
I also make all my ribbon cables using all 3M NOS Parts (Some Alpha/Amp parts too)
ROM Board Adapter Photo Album HERE
Ribbon Cable Press HERE
~Brad