The receiver alone is not banned by the features part of the law as it has no features until it is built.
It may legally be a "series" weapon, however, but to my knowledge, no court has yet decided that the receiver is a "series" weapon.
You can bring a aw to the prk if you can get the state to allow you to register it. The law allows aw's to be registered in the same manner that mg's would be registered.
The proverbial snowball in hell likely has a better chance than you getting the state to allow you to register your aw, however.
Build or buy a CA legal FAL. No flash hider and a fixed 10 round mag does the trick. You feed via a stripper clip dust cover and fixing the mag takes 5 minutes with a drill press, a tap, and a set screw. Converting it back is even simpler should you move or a miracle happen and the laws get repealed (ha): remove the set screw from the mag catch.
That or an M1a are your best choices right now in the prk.
Ray