MAD-1 replacement ?

I've been reading through older topics to see if I can find my answer but haven't had any luck. Does anyone know if there is a chip that can replace the mad-1 ? I see some sellers saying that they have all new boards and chips in their games and I've got all the rest figured out except the mad-1. What commercially sold chip can replace this ? If there is a topic I've missed please point me in the right direction. Thanks in advance.

Reimplementing the truth tables of the MAD ICs using discrete logic (using nocash's documenation as reference) would be straightforward, but somewhat tedious and would use several ICs.

On the plus side, you wouldn't need to support the MODE input, because any given PCB would always run in Mode 20 or Mode 21 all the time.

We actually already had a complete thread about this.

Thanks for pointing me in the right direction.

Locked topic; see thread referenced by lidnariq.