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
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.