I bought some more games:
Entex Soccer: TMS1000NL MP0158 MS^7923
Super Sports-4: MP1219 MSL ^8014
ELECsonic Football: MP0170 MSL ^7936
Conic Football 2: MP1181 MSL ^7945
Conic Basketball: MP0168 MSL ^7949
Coleco Bowlatronic: TMS1100NLL M34014-N2 WES 8109
Coleco Head-to-Head Basketball: COP420L-NMY/N
Mattel Invisible Alien Neutralizer: COP410L GZW
Mattel Basketball 2: 2x COP420L NMP and NMQ
NSC Quiz Kid Racer: MM4799 DUZ
Mattel Soccer: MM4799 NFR
That makes 4 MM4799s so far, and I bet Mattel Hockey also uses it. I'm hopeful that Quiz Kid Racer has similar ROM contents as patent US4051605. That patent looks like it's for the same calculator, but you could connect 2 of them together to compete, and the actual calculator doesn't have any connectors.
I've also got Talking Computron and Parker Bros Lost Treasure coming.