The title is 'Street engine on a budget'. Well, you need to specify your budget, because aluminum heads and roller cam setups are certainly not cheap.
If you are truly 'on a budget', there are less expensive options. Of course, if you can afford to throw down the big buck$$ for edelbrock RPM heads and a roller cam & retrofit roller lifters, go for it. Those are very nice parts.
If you want to spend alot less money, here's my suggestions:
Vortec iron heads have 64cc chambers and flow well. 'Dirt cheap' vortec heads, casting 062 or 906 can be found in the junkyard off of '96-99 suburban/yukon, trucks. Or, if you prefer, here's a set on ebay: http://www.ebay.com/itm/321567563063
Swap in used LS1 beehive valve springs with comp 787 retainers to increase the vortec head's lift capability. Just be cautious and inspect used vortec heads carefully for cracks. They are prone to cracking in the exhaust seat if the engine was overheated. Use the stock vortec self aligning rockers. At the junkyard, also grab the head bolts, center bolt valve covers, and valve cover bolts too.
Throw it together with a ebay vortec 4bbl intake: $118 http://www.ebay.com/itm/121404952728
and then consider a summit cam/lifters. Good cams, with proven grinds for cheap. I'd consider 1102 for auto, 1103 for manual trans. On a street car, there is not going to be that much difference in power roller vs. flat tappet cam, but there is a big difference in price!
As far as ignition, you don't need the fancy MSD stuff. Run a HEI, also easily found at the junkyard from any mid/late 70's - early 80's SBC.
Score some cheap headers from craigslist or a swap meet. I scored headers for my '68 for $40 off craigslist
The standard oil pump is fine. Don't need a HV for the street, just robs power to be always pushing against the fluid when you don't need it.
You'll have a rippin' combo with hundreds
invested... instead of thousands
This is coming from a full time college student, shoestring budget guy. If you have more money for all the best brand new parts, go for it, but my point is you don't have to spend alot to have a stompin' street engine if you are careful and know what you are doing.