MAK-90 ("Modified" AK 1990 ) These are china made rifles and are of VG quality. Normal configuration is the thumbhole stock and no bayo. Excellent shooters and sell for $300-$350 (Stamped) $400-up (Milled).
The Pre-Ban Norinco AK: China made in pistol grip configuration will cost $800-1100.
Polytech AKS: China made from arsenal 386. Best post-ban AK available. Thicker barrels w/ cooling ribs, super sweet trigger group, thickest (stamped) receiver and blue finish. $329-$399.
*The Pre-Ban version of this rifle will have the threaded barrel and bayo. $999-1200.00
SAR-1: Romanian AK with U.S trigger parts package. The 1999 rifles had some trigger and hammer problems but have been pretty much ironed out from 2000-on. Good reliable rifle with matching wood and average finish. $250-300.
SAR-2 : Same as above but chambered in 5.45x39
SAR-3 : Same as above but chambered in .223
WASR : Same as SAR-1 but was converted to take standard hi-cap AK mags. Some can still be found in the single stack mag configuration. $250-285
Romak 991: Same as WASR but remains single stack mag only and has thumbhole stock. $250
Maadi: Egyption made AK with U.S trigger parts. Terrible finish, terrible quality control and terrible wood. I would avoid these.
These are just a few but I hope it helps some.