If you're looking for a no nonsense, no auto focus, no frills type of 35mm SLR, I'd suggest checking out an Olympus OM1 or something similar from that time frame. I shot exclusively with an OM1 and a handful of lenses (primarily the F. Zuiko 50/1.8, which I really like) for probably 4 or 5 years. My dad bought the camera the year it came out (1972) and besides having to reseal the camera due to age and deterioration of some of the foam, it never had a single issue. Sub zero temps, 100+ and humid, dropped that shit a few times, drunk people mashing into it at concerts, whatever. It always worked exactly how it was supposed to. You can find the body + the F Zuiko lens for pretty goddamn cheap. And if 50mm isn't your thing, there are a million lenses that will work on it for cheap. And a million more if you're willing to buy some adapters. It's also worth mentioning that even though it's an SLR, it is not some monstrosity of a camera. With a short lens like the 50, you could definitely fit it in a jacket pocket. Hell, you could fit it in your pants pockets if you carried the caps and pulled off the lens to pocket it.