Maybe I'll just stick with the Military Classic from Wolf. Or I can move up to Federal or Hornady. In those countries that still use this 7.62 ammo in combat what brand do they purchase from for their armies?
Basically, any of the steel cased stuff is from a former Eastern European Military Factory somewhere. The Soviets built factory cities to supply WWIII, and built multiples of what they needed expecting most of them would be nuked. They also built ammo factories as foreign aid. Tula is its own factory. Barnaul makes the Bear ammo. Wolf used to be made by Tula, I don't know who makes it now. Ulyanovsk, or maybe Tula again? At the end of the day it all goes bang. AKs were designed by a genius to be manufactured by peasants, maintained by idiots and shot by children. No need to overthink it. I'd just get this:
http://www.sgammo.com/catalog/rifle-ammo-sale/762x39-ammo
Federal and Hornaday, are probably the few examples that were not built to Mil-Spec. I am sure they work just fine, they are respected commercial manufacturers. However, I don't see the need to spend additional $$$, unless you have a nice 7.62x39 bolt gun.