I guess it really depends on what parts you choose...
I paid just under 400 for my exhuast work in total, and that included 2 12" glasspacks and an H-pipe which I havent had installed yet. So I went:
CAI: 250 (any more is unreasonable)
Tune: X-Cal2+tune should be like 550 or so
headers: 300 for MAC Shorties.. could probably find them cheaper somewhere else
T-Lok: 150 for gears + 150 for T-Lok, so 300+ 150-200 install? So lets say 500
So thats around 1500ish. 500 bucks headroom..
Stage 3 Port & Polish is only 900 bucks from SuperSix Motor Sports.. that'd be my next goal. Includes fully ported Intake and Exhuast ports, full bowl work, 1.81/1.54 valves, 3-Angle job, springs, seals, surfaced, and assembled.
You're really talking a good 13 second car now! Port & Polish + tune should be good for ATLEAST 45-50 rwhp