the best bang for the buck? why, the slutty ol' romanian sar-1 in 7.62 x 39, the sar-2 in 5.45 x 39.5 and the sar-3 in 5.56 x 45. they ain't so pretty but they run hard and long for ya.
the vepr is a step up the quality ladder. a tad on the heavy side, they are well made, abeit a little funky in styling...still a reliable kalashnikov action in an rpk (heavy walled squad light machinegun) receiver. genuine russian love made at the molot factory.
the vepr's are also available in 3 calibres and both 16" and 20" barrel length from robarms.
also, check out the ,milled (type III) variants from arsenal in las vegas. a blend of bulgarian craftsmanship and american marketing, they are very well built and come very close to a true ak-47.
other than that, the russian saiga clones built by marc krebs and ak-usa are worthy of consideration. no 5.45 in that lineup, but still, very nice rifles on the whole.