Pls recommend source for full AC system for non-AC 1971 5.2 L Duster

Classic air. Honestly if you are looking for a do it yourself. It’s not perfect but it will work.
Being in FLA have you tried to find an ac only install shop? They used to be popular but with the fact most new cars come with ac now standard. Possibly not so much. Showing my age there.
Syleng1