I love the little 383's. You can pickup complete 383 cores for $50 all over. I just dropped off some stealth heads, .567 roller cam and 1.6 MP rockers for my new 383 to the engine builder this morning.
Mine is very similar except I stayed with a stock stroke, 12 to 1 compression, M1 Single Plane and solid roller cam. The builder is estimating it will make over 500-550 HP but I'm skeptical.