your best bet would be something small like the rt cam (from what i heard and can also tell you about it--its not worth the metal its made out of), the r/t+10 cam, or something light to moderate from hughes or socal, or krc maybe. i think mancini racing also..
http://chucker54.stores.yahoo.net/camshaft.html
pretty pricey for one step about stock imo.
with any cam change though, you want to be certain that the springs are up to the job though. to light a spring, and the valve will float, then bam.
if you plan on changing all the hardware out later, id just get the cam, then the other things once you get the coin for them, then do the whole job at one shot. be alot better on ya to do it that way. this way your nat tearing into stuff 2-3-4 times.
i have a hughes 1418aln, springs, locks, and retainers ill let go for a total of 500.oo plus shipping.
you will need those roller rockers to clear the new springs though. so price that with a new set of rockers...looks like 304.oo at mancini for the adjustables (SHP-S70036A). not a bad amount IMO.