Turbocharging the LT5 in 2015

[Bob Eyres]

What with all the turbo cars, stock and aftermarket, running around today, and the fact that it's been over a decade since John Lingenfelter developed those legendary turbo LT5's. It makes me wonder how expensive a modern version would be.
Later model turbos have to be more efficient, effective, and cheaper. The electronics are undoubtedly better, easier to tune, and cheaper. I know the plumbing is a serious challenge, but why are these things so expensive to build?
Would it be possible to come up with a kit for the stock block LT5 that would be in the same cost bracket as say a Haibeck 510 hp. engine?

It just bothers me that all the forced induction cars available now are so much quicker than our naturally aspirated antiques. Damn, my wife's grocery getter, (an eight year old, six cylinder, 335i), is nearly as quick as the old "King of the Hill".