I'd think twice before looking into buying a PPK .380acp.
Many pistol shooters get "bit" from the PPK's sharp slide.
I also read a detailed NRA article that did a T&E on several popular .380acp semi-auto pistols. None of these major brands did very well.
The PPK is widely known for feeding/cycle problems(jams) with carry-protection rounds too.
In 2012, you can buy a .40, .357sig or 9x19mm to protect you that is the same size/wt as a Walther PPK.