another AC question

[dads longhorn]

I have a 1971 C20 with AC installed at the dealer (not factory) back in 1972 or so. There is a long plastic unit under the dash w/ controls, vents etc. It's not in great shape but is workable. Also it quit blowing cold air, but the blower still works. I don't want to throw everything out, but is it worth keeping? Still has good knobs, and has all the stuff in the engine that makes it work.

Question, what should I do w/ it? Fix it, tear it all out? There's no need to do anything immediately, but down the line I want it to work or get it out/replace it?

I guess I'm just looking for ideas on where to go w/ this. It's not critical to have AC, but it sure was nice when it blew cold air.

Any ideas will help, thanks.