DB421.. I have the 15 X 15 RH prop, 1" shaft, on my H-34 and have been ok with it .. I replaced it in '08 when the original Michigan Sailor threw a blade (corrosion) .. The new Michigan Sailor 2 at the same pitch/diameter has been fine for the coastal cruising that I do .. ..
If considering a three blade prop, think about the Cambell folks. They seem to have a pretty good fixed blade product.. Whoever you go with, get them to recommend the diameter and pitch .. some props, like feathering or folding will need a different pitch than the original.
Hope you guys are de-iced up there now!