I just recently was given a 15' aluminum hull airboat with polymer bottom, steel cage. I was told the motor is a 280 h.p., 6 cylinder continental airplane engine, left hand rotation. It had a 2 blade 72 x 38 sensenich wood prop, need to replace due to dryrotted. Need help in choosing a good composite prop for it, and any information where i could find maybe a used prop. New to the airboating so I would like to do it right the first time.