hmm, Stiletto can you find out which other worth-to-emulate devices use the AMI S2000 series MCU? (I poked him on IRC so he knows I called him)
I was about to say "yeah, we acquired the datasheet/manual for the AMI S2150 a while back because of the" and then had to stop myself, because it had been Lord Nightmare who had asked me, way back in 2009, to look for it because it had been used by Wildfire electronic pinball. Ultimately, it was Bitsavers who acquired the data book, though I think I acquired the datasheet before them through other means.
Nothing has leapt out at me so far so I may expand the search to others in the S2000 family.