propeler

I have restored a 1974 matinique. I have had rebuilt the original 302 c.i.d. 4 barrel holly motor. I have increaded the compression, and beefed up the cam a bit. Maybe added another 50 h.p.from 220 to 275 h.p. By the way, the boat is 17' 9" and 2200lbs.   The prop on the boat is a 12" diam. 15 pitch, right hand three blade bronze prop. { most likely original } This prop. is worn and needs replacement. Should I go with the same or can I get more performance out of a different diameter and pitch? I am inclined for more speed vs. "out of hole" performance. And, what about a four blade vs. the three blade? stainless vs. bronze? Finally, best place to purchase.

Rick