I had one years ago. It's probably chambered in .38SW. The Hong Kong police caried these revolvers back in the 50's I think. They transitioned over to the S&W revolver and these went up on surplus. I found mine in a pawn shop back in the early 80's for about $125. The finish was well worn, but it locked up tight and turned out to be a nice little revolver. I bought a .38sp cylinder from GunParts and had it fitted. Till I sold it the PP served as my go anywhere, do anything gun.
Gun Parts also made cylinders in .32 mag and 3" .32 barrels(or perhaps they were "left overs from the Cobra/Det Special in that caliber). I can recall reading an article on one of these conversdions from a "Hong Kong Police" 38PP & the conversion was a great little "companion gun" as Majic said. I wish Id bought one of the cylinders. I have a Courier,and the alloy cylinder is "saved"and a steel one resides in it. Be even better with a .32 mag! Bud