The SuperTigre G-75 should work out well in your Corsair. Just make sure it's well broken-in before you put it into the Corsair. You may want to fly it for a few gallons' worth of fuel in a sport model first, to get it well run-in. Once it's broken in and set correctly, it will run well in almost any mounting attitude.

For a 3-blade prop, maybe an 11 x 8 would work. It's hard to say. We normally run a 12 x 7 or 8 2-blade prop on this engine, so the 11 x 8 3-blader may work. Please remember, though, that 2-blade props actually work better, and you can't tell what's being used when the engine's running. If you want the "looks", then make a scale prop for display purposes.