The CZ vz.52/57 is a late production variant of the CZ 52 rifle, chambered in 7.62x45mm.
The Soviets pressured the manufacturer to make it compliant with the AK round, so the newer rifles were so chambered.
Production of these rifles halted in 1959.
It's going to be tough to find a model in 7.63x39... relatively few were made, and those weren't very accurate or reliable. It was designed for the larger, more powerful cartridge, and the difference in functioning was readily apparent.
You can still find a good CZ 52 in it's original chambering, though... and they work just fine, and ammo is pretty cheap.
I never even thought of the bolt actions... I immediately flashed to the CZ 52! Gettin' senile, I guess, but I just saw one this weekend... interestingly enough, it had a new plastic stock. Didn't know anyone made them (for the CZ 52).
I DO know a couple of guys with the new bolt rifles, though. They love 'em... but then again, CZ has ALWAYS made great stuff!