Most furniture should be interchangeable between stamped AKs from various countries, or between milled AKs. Guns with stamped receivers take different butt stocks than milled guns.
There are some "slant cut" MAK-90 Chicom AKs imported into the US which require special butts if you're going to convert them from a thumbhole to a regular stock.
Yuogslav stamped rifles have thicker receivers than other countries' stamped AKs, so stocks and forearms are not interchangeable without some fitting, AFAIK.