I've encountered this enough it's starting to get annoying. I've been running in to situations with the '05 GP and I'm seeing the same with the '04 where they just don't make the parts.
Examples :
Can get rear end strut assemblies, but nobody makes ready to go front end strut assemblies. Can get the pieces, but not the whole deally.
Can't buy complete replacement control arms. Tons made for every year before and after but us 04-05'vers. Can get the bushings but not the whole deally.
What gives? Is there anything else I should be aware of to give me reason to throw the thing at a dealer and drive home a new Camaro?