You could always do what I did, stick some 96 heads on your car and open up the scoops.

I do have an air cleaner base that I believe to be a correct PR, it is slightly different than the PP one I have for my latest project. The main difference being the snorkel dimensions are a little narrower at some points. I'm not sure if the variation is intended(perhaps different suppliers of the part or maybe they varied between Firebird and Camaro as they went down the production line) nor if either part I have is correctly identified. I do believe when I stick it on the car, no one will question its authenticity.

I also have a Pontiac air cleaner base for a 350 engine. Again, not 100% certain of its correct application.