I can speak for sks a bit. There are Russian, Romanian, Yugo and Chinese aka norinco sks rifles. All but the Yugo have chrome lined barrels which is nice and only the Yugoslav have the grenade launcher on them.
Be prepared to pay a premium for Russian and Romanian sks. In the current market $500. I have seen norinco a go for $275-400 in my area and Yugo about the same.
Also consider the norinco sks M or D model which will take regular ak magazines. I would avoid the duck billed mags for sks, they are usually a pain in the butt to change out if you can find a one that is reliable. Good hunting!