BBC Exhaust manifold options?

[TCONNELLY]

After reading here about the pros and cons of cast manifolds vs headers, I would like stick with cast manifolds. It seems there are options for the SBC engines, mainly Ram Horns. I have a 1972 C20 with a 402 that I would like to get a bit more flow out of the exhaust manifolds. Can anyone recommend any options for the BBC? Perhaps Chevelle or Corvette manifolds that will fit and not cause any interference issues in the engine compartment?

I'm looking to get more power out of the stock motor. My plan is for a mild cam, freer flowing exhaust, new intake and carb, and HEI. I hope this plan makes sense. The 72 motor is low compression 8.5:1, can I still get some power out of it, or do I need to do something to raise the compression? Not looking to build a race motor, just something with some nice power and torque, and a good sounding exhaust. Is 300hp realistic, with some mild mods?