I'm building an AR-10, and have a PSA PA-10 upper that is fully completed.  I also have the lower parts kit, and a PRS on order.  Basically, all that I need is the buffer tube, buffer, spring and stripped lower.  (And a nicer trigger, but that's not strictly necessary.)  I had planned on going PSA upper and lower just to avoid compatibility issues that plague AR-10s.  The problem is that I've had a stripped lower on order for over 8 months now through a local gun shop, and they've been calling PSA up every 2-3 weeks and asking about it, and are getting blown off.  I know that they're making them, because I've seen complete lowers on their site, but they're all with the carbine buffer and stock.  I'm not building a carbine and don't want to spend an extra $150 for parts that I'm never going to use.  

Does anybody know of another brand of AR-10 lower that is compatible with the PSA upper that I have?  FYI, they use different pins than other DPMS pattern rifles.

If you have a gen 2 upper then keep waiting for the gen 2 stripped to come into stock...

PRO-Fab from AimSurplus is advertised as compatible with PSA rifles. Not sure how the cosmetic lines will line up between gen 1 and 2 uppers....