Once you start talking about new, performance 4.6 heads, there really are'nt any cheap ways to do it. Reasonably, I'd say VT.
Check these guys out: www.modularpowerhouse.com
VT and MPH are some if the best around but if your looking at price Patriot Performance is a cheaper setup. Alot of people talk about poor quality from them but a friend of mine has them on his 96 Turboed GT and loves them.
I'd say just have a good local port them. That'll probably save you about a grand. As far as cams.....N/A = VT St.2's & Power adder = VT St.2/3 blowers. Or give foxlake a call and get some custom grinds