"I have no idea if they are still available on the civilian market."
Yes, they are. You can buy the civilian version of the AK 47, or the MAK 90 which is the AK but with different woodwork. I have two MAK 90s in 7.62 X 39MM, and I have Chinese SKSs as well. They are nice guns.
The thing I like about the AK-47 and SKS is the exceptionally smooth trigger pull right out of the box. The AR-15's I've tried, seem rough in comparison. Trigger pull is important when it comes to hitting the target.