header suggestions

[GM Muscle]

i have a 69 camaro, engine wise i have a set of angle plug pro action 235's on a mild compression 355 with a fairly large cam and a milodon kick out oil pan. chassis wise i have a stock subframe with lowered solid body bushings. its a power steering car(iroc) with no a/c and its lowered. i was wondering what you guys would recommend as far as headers go. As of now i have patriot mid lengths which fit ok but i really feel im hurting the power and intake charge with the small diameter, short length primary. the main reason i switched from long tubes was the ground clearance issue and the angle plug problem. im going to say my car makes 450-500hp. Are there any decent headers out there that offer a decent fit and ground clearence? what diameter of primary should i go with? surely i wont have to spend a grand on some decent headers.