The Retina IIa can be a little finicky at age 50. All three of mine are awaiting repair. I would go with one of the Japanes RFs or maybe something Soviet. The Kiev 4a can be very good if your hands are big enough to handle the "Contax grip". Also worth looking at are the Fed 2,3, and 4 and the Zorki 4 and 6. One of the lesser known Japanese models that usually goes for a song is the Petri 1.9. The lens is decent and the rangefinder, viewfinder, and overall ergonomics are superb.