Anyone have experience with blown small blocks? I have the opportunity to trade for a 377" small block with a ton of high end parts on the top end. It was built to be a pro charged motor and currently only has 8.5-1 compression.

I'm looking at getting it around 11-1 compression, and putting a 192, 6-71, or maybe 8-71 blower on it. What kind of power could be expected with this combo. Also, I don't want to run so much boost that I need to O-Ring the block, etc. I do run alcohol, and I'd like to get around 1000 hp if possible in the future.

OR......would I be better off to just run a pro charger? If so Why?

1000 HP.
While you are changing pistons get the block and heads o-ringed. Hoops are even better.
871, crank support, magneto
Your future self can thank me later