What I did was put in one of the later ones from Chryslers/Jeeps. Inexpensive on eBay. Same basic radio but also plays cds. Good enough for music, specs are better than almost all ears (better speakers are the key). Plug and play.
However, I think I've still got the original from my 91S, as well as the touchscreen version from my LS.
Great ! If you find them are you able to post some photos? I am definitely after the original Alfa one(s).
Also...any way of testing they still work all OK?