Bulgarian AK-74 kit requires 6 US parts to be 922r-compliant (due to the threaded barrel/muzzle brake).
The Shephards crook replacement from Red Star Arms doesn't count as a part of a rifle.
The parts in a semi-auto AK are listed here:
http://www.ar15.com/forums/topic.html?b=4&f=93&t=55169
The RSA fire control group counts as three parts (Hammer, Trigger, Disconnector), the US-made receiver will count as one part, and the US-made stock set from someone such as K-Var (
www.k-var.com - join their forum, and get an additional discount) will count as another three. After that, you're one ahead of the game, as your rifle would have 7 US-made parts and 9 foriegn parts.
There's a couple other options you could do.
US-made trigger = 1 part
US-made disconnector = 1 part
US-made hammer = 1 part
US-made receiver = 1 part
US-made gas piston = 1 part
US-made muzle brake = 1 part
US-made buttstock = 1 part
US-made pistol grip = 1 part
US-made forearm (top AND bottom) = 1 part
You could mix and match any of those to come up with the 6 parts you needed.
Most people here would reccomend you get yourself an RSA FCG, as they're reputed to be the best (I own several of them now, but need to wait until my rifles return from the gunsmith before I can comment on them...). =)
The AK-74 builds that I'm doing are utilizing an RSA FCG and a K-Var US-made black synthetic stock set. To me, it seems the easiest way to go - I'll keep the Bulgarian brake and the Bulgarian gas piston on my rifle - if I need to swap later, for whatever reason, I'll do it, but I don't see the need.