What are some cheap semi auto rifles that shoot 5.56, 7.62x39, and 5.45x39

[henschman]

The Saiga comes in all of those calibers, and is a very high quality rifle. If you want something cheap to shoot, the 5.45x39 is particularly cheap right now.

 

[rocinante]

Last year I bought 2 century vz2008, vz58s, for 360 each. Best value ever for a 7.62x39 semi auto rifle. They bumped the price up to around 500 now though.