As far as the whole totem pole goes, you've got your Romanian imports from Century (WASRs), then those from Lancaster Arms and the like. About equal with those would be MAADIs and other more unique models, though they wouldn't be former Soviet bloc. Next up you have basic Saiga conversions. They run about eh... what, $600?... for a decent job from some guy who wants to sell his. Next step up are the stamped receiver Arsenals. At the top of the ladder you have Saigas that have been completely converted to look and function like an AK-100 series rifle, as well as milled receiver Arsenals. Beyond that, you're looking at rare pieces from before Bush 41's import ban and pre-86 NFA items.
I'd recommend a Saiga. Comes from the same factory where Mikhail Kalashnikov works. Made of brand new parts, not surplus. Doing a little work on them (if you have even a little bit of skill at a workbench) will render you the best AK for the dollar. Us snobs like Saigas because of the pedigree.
As for Arsenal, that's a little higher up the price ladder. If you want to get a milled receiver, knock yourself out... though there isn't a huge advantage in having a milled AK over a stamped one, save the parts seem to move against each other more smoothly. You'll be well served by a stamped model as well. I wouldn't call the milled versions worth the extra money, but to each his own.