Go for the Rolleiflex 2.8 (or 3.5) E model. If you're used to shooting all manual all mechanical cameras, they'll fit like a glove. And an E in decent working order isn't that big of an ask either - both of mine were purchased for under $600. The one needed an overhaul, which was a little pricey at $400, but now that it's done, it's like butter - focusing and setting shutter/aperture are silky smooth, focusing is dead accurate, and exposures are dead on what I set them to (no accounting for user error). The other one was perfectly fine for a couple years before it too needed servicing, but like the first one, now that it's serviced, it's nothing but a joy to use. And they can take heavy use too - I just put 70-ish rolls through one of mine on my Italy trip.