All comes down to mechanical condition, I say. 4" heavy barreled K-frames are the cat's pajamas, .38 or .357.
I don't place a premium on .357 capability when there's a .38 load for every occasion out there, from nice little cream puff match wadcutters to mid-level .357 numbers making Buffalo Bore Heavy LSWHPs, and everything in between, more of it, easier to find and generally less expensive than .357.
If either of those 64s is mechanically sound, $300 is about the best price you're going to find anywhere these days. I'm not sure the 65 is worth the extra $150 that could go to ammo and range time.
If you're seriously in the market, I'd run thorough mechanical checks and leave with whichever one had the best specs.