Mags should usually fit between models, but the russians changed quite a few things over the years, so a late versian russian (55-56) should be most similar to early chinese.
The chinese also changed things over their toolings lifespan like stamoed instead of milled parts, pinned barrels, etc.
In my experience i know that chinese gas tube/piston that i got as an extra was close to 1/8" too long for my 50 russian