As I understand it, the Russians actually designed the original AK47 with a stamped receiver but had problems initially with welding the guide rails for the bolt carrier and had to go with a milled receiver. They later perfected the manufacturing of the stamped receiver and produced the AKM.
Look for a factory built, stamped receiver AKM rifle. Chinese (Norinco) is your best bet if you want high quality at a reasonable price. There are a few on Gunbroker right now that are quite reasonable. If you are patient, you can find a fixed stock version for under $1000.
The Romanian WASRs from Century Arms can be great shooters but the fit and finish is not great. Keep in mind that these are imported as low capacity sporting rifles and then made into high capacity, 922R compliant models by Century - not a pure factory built rifle.
Century quality control is horrible so make sure you buy it new from someone that has good customer service as there is a good chance you'll have to send it back to be fixed/replaced, particularly if you are new to the platform and don't know what to look out for before purchasing. The good news is that Century is so used to dealing with returns that they rarely ask questions and are very good about replacing crooked or otherwise buggered up rifles!
You can also find affordable AKMs that are built from de-milled parts kits on US receivers (and other US parts). If you can find a reputable builder, you can get these for about the same price as Century guns but with a little higher quality.
I had a local builder put these Romanian AIMs together from some nice Romanian Civil Guarda parts kits. He picked the kits with the nicest finish and left it original. I got a very good price on a trio.
By the way, those AK pistols are pointless, IMO. Too big and heavy for a pistol. Needs a stock.
