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You are looking in the realm where there is little information. That being said you will want a large diameter prop, about a 16 1/8". The pitch will be more difficult, a prop of about 13 to 16" pitch should work. The lower pitch may be better for you. I would also recommend a stainless steel prop to take the torque.
I would have your local dealer call Yamaha and see what they recommend as well.
Hopefully this gives you a good starting place. Let me know if I can help further. Thanks