Last month I was at a show, and a guy had a nice looking machined reciever AK for sale.  Wood stock AND pistol grip, no baynoet lug, and straight muzzle.  He said it was some company who made them briefly right after the ban, then no more.  It was not a Norinco.  It looked like a Bulgarian or Yugo.  It was NICE - fit and finish looked very nice.  BUT, could this be an "illegal" conversion?  I suppose it is hard to tell, unless you can strip out the parts.  (He wanted $600).

there were some post ban rifles with milled receivers, i'm not to well informed but i know that some had thumbholes and were easily converted to pistol grips.
to legally have a pistol grip all a post ban milled gun needs is 4 US made parts, 5 if it has a muzzle attachment.  easily achieved with the abundance of US parts currently available on the market.