Cherokee Gun and Pawn does FFL transfers for free. Or are you just looking to purchase a cheap lower? If looking, just go to the gun show this weekend at North Atlanta Trade Center. I have seen them below $100 there. PM if you want to go and meet up.
I actually have a completed lower i am looking at buying for $120 shipped. So thats the way i was leaning.
I'm guessing it's got to be one of the polymer ones. 120 is almost impossibly cheap for a complete aluminum lower (new, anyway).