You should have a typical Delco CS130 alt, GM.
You actually have more options than the HO guys...........you may have to reclock one, but that's easy.
I used a '86 Capice alt, 105 amps, before I got the Powermaster, which I highly recommend.
I have the 2.5 which uses the small case, you should have the larger case......again, more options.