It would help if you could provide a close-up of just the 1st stage - preferably from the side and not the end. At a guess it could be a MK5, MK8, MK10, MK15 or ? from the 80's up to the Mid-90's. Do I see a black plastic fitting where the Yoke meets the reg body? If so it could be a MK5 spec 2nd generation, A Mk10 spec 2nd generation or even a MK15. If we assume the black knob is original, they only really started using that in about 1988 or later - before that it was a chrome metal knob.
The 2nd stage is a G250 "Mardi Gras" vintage 1994-5 which leads me to believe the 1st could be a MK10. Or possibly a MK15 if the 1st stage is Matte and not Chrome. I believe it has a flat bottom also?
The other looks like a G200 with a "Red" Option. The default for that was a black cover with a blue sticker on the purge which it looks like is sitting there also. 1988-1995 so it could've been paired with the Mardi Gras.
It could also be an R190 since they're the same vintage as the Mardi Gras also but we'd have to see the front of the cover to determine that.
If it says ScubaPro between the compass and the pressure gauge, we can safely assume that's one of their original consoles. The computer would be "iffy" IMO. And you may find that they'll want a fortune to change the battery - if you can even find someone who will. Later models than that cost $150 to service at the factory so it's really almost cheaper to chuck the console and buy a new computer.
All should be serviceable except maybe the computer. Older SP regs than those are in use daily.
Post more close-up pictures of each piece - that will help. Usually the purge buttons on the 2nds were marked with a model # and some of the 1st stages are also - often embossed in the yoke just below the knob.