[WSSix]

Correct, you can't put GenIV heads on an LS1. You'll need to stick to ported LS6 heads if you want to maintain a budget. I'd check out Texas Speed and Performance. They have budget ported LS6 heads that will work really well. LS6 intake is a must because it works very well. Ported oil pump should be in there too. 1-3/4" long tube headers if you don't already have them. For cam, you have a ton of options. You just have to decide where you want to make power or what kind of idle you want. I'm assuming this is a T56 car as well. If not, spend money on a torque converter instead of the cylinder heads if you're pushing how much you're wanting to spend.

Also, upgrade your pushrods to one piece units. Factory rockers are fine.