PWAs were all machined from forgings (good).  However, none of them were sold as complete factory rifles, so proving preban status is difficult.  Also, since PWA no longer exists, it isn't possible to get a lower repaired/replaced and retain its pre-ban status.

Olys were (and are) available with both cast and forged lowers.  Oly still exists and will remanufacture pre-ban lowers on a new forged lower.  However, they lost their records due to a series of fires and a flood (and poor storage practices), so they can't really verify pre-ban status either.

-Troy