If you want something SRL-like, you might consider getting a genuine SRL setup. You can get Nikon F bodies and lenses, wonderful equipment, for next to nothing. Do an e-bay search for 'Nikon F' to see some what I mean. I didn't even bother to do a similar search for 'Nikon FTN' because I knew it would just break my heart. I've put together my dream system in camera shops, where the owners are generally thrilled to give fine equipment a good home and so cut some great deals

The two downsides, of course, is that these are film cameras and don't do anything automatically. You have to be able to focus and set your exposures manually, which is about the equivalent of walking and chewing gum at the same time but clearly few people today are willing to do it.

You'd also have to scan your images, either slides or negs, before you could do anything digital.

I've compared using these old systems to using tube amps, old mics etc and there is something of that to it. There are genuine technical advantages though: you have absolute control of the focus, shutter speed and aperture and there is a vast range of high-quality lenses and other accessories available for peanuts.