Have you managed to get pricing on individual parts, like the crank, rods, and cams from the SRT6?

I don't know, I think the crossfire is a great platform to build on, it's just the initial costs of making more Hp will cost more than most other cars.
But then there's the handling of other vehicles, which most may never come close to the Limited XF's suspension or brakes, so then you end up spending more in that area instead of engine components. So in the end, if you want a race car I think everyone pays about the same amount to be at similar power or handling levels.

Well, I've been scoping out the 350Z forums, and those guys are using Vortec kits on their motors. The tuned S/C setup for 350z with labor will run you about $7,000, and that's only the kit installed with dyno tuning. I don't even think that motor has a forged crank, and it's not even using a supercharged camshafts, (tag on another $2,000 or so for that), so IMHO the SRT6 crate motor is the way to go if you want to get boosted!!
The srt6 has been engineered for boost, so who knows how long those 350Z motors will last with a vortec set up?