Re: mercury props
It's not a bigfoot if the motor is that old. What kind of performance are you currently getting out of your propeller? We need to know wide open throttle (WOT) RPM's and current propeller size and pitch.
Generally if you want a prop purely for water skiing you want to go one or two sizes less in pitch for a little extra pulling power but you must make sure you are not exceeding your maximum WOT RPM limit.
Without knowing what you currently have it's impossible to make any kind of recommendation.
