PA63 is a very simple defensive pistol thats been in service for decades. They are very reliable and powerful for such small sidearms.
They are very very similar to the CZ 82 George mentions. Except the 82 is double stack holding 13 rounds and the mechanics are far more complicated on the 82. You gotta know kung fu to get em apart and back together again.
The pa63 is singlestack 8 rounder true to the original makarov design and very simple to maintain. you would be hard pressed to find a more reliable milsurp type sidearm.