I would actually bump up the compression some and choose a bigger cam. I would also recomend going to ISKY instead of Comp for a cam, unless you want a custom one, then Comp will do nicely but make sure you have someone else look at their proposed cam specs, IMO they go after chasing peak power too much and give up too much midrange- not where you want to go. An RPM intake will do fine. If you want to run roller lifters I recomend starting with a roller block and just running the LS lifters, they work very well and are only $100 a set. With more cam and compression you could come close to 500hp and still have what I would consider a relatively mild engine.
Doing this all for 2G's will be very tough, you'll have over a G in the heads and cam alone. I would set your budget to 3G's.