OK...forget about DSS racing and CHP. I was looking at their websites and the prices for their short blocks aren't too bad, but the long blocks are way too much for what you want to spend.
I can't find the web site for Central Coast Mustang(CCM), but here is a blurb from a tech article in 5.0 mustangs and superfords magazine explaining what I was talking about above about CCM.
"Several variations of the assembled short- and long-blocks are offered, including a $1,895 version built using a new block, a new Ford crankshaft, new Ford connecting rods, new hypereutectic pistons, and new GT-40P heads. This combo arrives at what is essentially an all-new ’93 GT-40 engine fitted with either a B303 or an E303 cam. CCM rates this engine at 320 hp, which can vary some depending on whether it is dressed with carburetion or fuel injection, of course"
Here is a link to that article:
http://www.50mustangandsuperfords.com/techarticles/86598/