26Sonic - I used your actual test data, and a 650 HP engine that I built by adding a centrifugal blower to a 502 MPI on Desktop Dyno. Because of the small cam in the MPI engine, I had to use 8 psi, not 5 psi boost. More cam and a bit of head work would help this engine a lot.
Your speed would be about 85 mph @ 5000 RPM with 28" pitch. Going down to a 27 " pitch would still be 85 mph at about 5200 RPM. You would likely be happier with the bottom end with the centrifugal blower by using less pitch. This is assuming a 3 blade prop doesn't blow out. If it does, then a Bravo 28 might be your best bet.