The VEPR series of rifle is based on the AK design. The VEPR is a civilian legal, US available version of the Russian RPK light machine gun- basically it works like an AK, but it has a MUCH thicker, heavier barrel and receiver and is manufactured to much higher tolerances.
The VEPR is available in four calibers: 7.62x39mm (the original AK-47 caliber), 5.56x45mm (the AR-15/M16 caliber), 5.45x39mm (the AK-74 caliber), and 7.62x51mm (.308 NATO). The VEPR also comes in 16" or 20" barrel versions. You can option it with a folding stock, muzzle brake, skeleton stock, tactical grips, ect.
My VEPR K is a 16" barrel 7.62x39mm version. It is just as accurate as any AR-15 I've seen shot out to 150 yards. Ammo is cheaper and it's WAY more reliable- after several thousand rounds it's never hiccupped. I paid $550 for it two years ago.