If you want one, go ahead and grab one.
You may want to check around, specifically at bigger pawn shops, to see if anyone local is a "dealer" for any brands. One of the shops near me is a Palmetto State Armory dealer... if I order directly through the shop instead of online, I don't pay a transfer fee, and they will meet the online price. Sometimes they have it in-stock (a stripped lower, for example), and I buy it that day. Sometimes, I have to place an order and wait for it to come in. Either way, I no longer buy an Anderson (etc) lower, unless the cost + transfer fee beats the PSA price... which hasn't happened as of yet.
The pros here can correct me if I'm wrong, but my understanding is this:
- a lower is a lower, as long as it's in spec.
- the lower (as of today, who knows what the future brings) is the only part that needs an FFL
- the upper, as long as it fits on the lower, will run as it's intended
- You can put a Colt, Daniel Defense, PSA, BCA, Radical, etc upper on a lower.
I've got lowers from Radical, PSA, Karri's Guns (that was $125+transfer, before I knew of the PSA deal), and I can swap everything around and it all runs fine. Some were complete, a couple PSA's were stripped with the cheapest parts kits I could find. All are milspec, the only difference is the rollmark and finish (and the finishes are comparable).
The way the laws are today, if I were just starting, I would buy a couple of stripped lowers (PSA), at least 2, and build one as a rifle and the other as a pistol; or alternately for the price I would get one complete pistol and a stripped. I would not buy a complete rifle, nor would I buy a complete rifle lower.
I guess, to future-proof as best as I could, you might grab spare buffer-tube assemblies and barrels, in "rifle" format, for as many pistols as you own. Or at least, barrels.