Welcome to the forum @quarterdrive67 I assume your old one is toast. the OEM ones are hard to come by and are almost NLA. you might find one on ebay, but your best bet is to look at an aftermarket controller. there are two that come to mind and are probably the most common ones. EZ-TCI and US-SHIFT both make controllers for these transmissions.
if your in to fine tuning shift patterns EZ-TCI came out with a newer unit that you can change all parameters and shift points but both come with a hefty price tag.
in my 93 the original TCM is still in the dash. I have often wondered what it would take for it to work if I tried connecting it all back up. OEM connector is hanging there by the trans too. I doubt my laptop would read it to pull data or codes tho.