Cartech and ITS offer systems for stock applications. I bought my Cartech system used, so they are available. I built most of my current set up with used parts. I figure with the turbo kit, short block, heads, intake, cam, clutch, and fuel components included, I have about $5000 in the car. For the type of power it is capable of, that's fairly cheap. Hell, I only paid six for the car.
1990 LX Coupe 5.0 5 speed w/ 2000 Exploder GT-40 engine, P heads, mystery cam (F cam per previous owner) 3.73, and not much else. In the parts pile - UPR tubular K member, CC plates. Future plans - Megasquirt & On3 turbo system.