PWA on LMT tooling? lol... that's a joke, really...
Pac West Arms made lower recievers for people who wouldn't shell out the money for a Bushmaster or Olympic SGW receiver... they were much cheaper, wholesale on them was under $100 when they were in business. The fit and machining weren't the greatest, but the finishes were decent. The one thing that you could guarantee with a PWA, and why I think most people like them, is that all of them are pre-ban... afaik, but that doesn't matter anymore. Quality is probably on par with Vulcan (hesse)...
PWA was bought by Rock River Arms in the mid 90's.
How much are they worth now? Probably not much more than a new Rock River, Eagle, or similar lower receiver. Since the AWB sunsetted, their value is substantially less that it would have been a year ago, IMO.