I am in the same boat as you. Honestly get an L67 powered car, install the recommended mods and drop a pulley size or two. That will probably net you enough power.
You could also top swap an L36, but why not start with a car that already has those parts?
Turbo would be expensive and mostly impractical for your desires. I wanted to go down the turbo route and have been told constantly that for the 300ish HP range you should stick SC. The transmission is the week point though but lots of great threads about how to make those numbers and have a solid tranny.
