IP31 propeller options AUTOPROP, FLEXOFOLD? Any 31s with feathering or folding?

My fixed 15RH12 is showing its age, with pitting and odd sounding from what our diver has told us. 
Our IP31 has a newer 3YM30AE, and after being in contact with several prop manufacturers, things get more complicated with questions as to distance from rudder, and clearances in general. Boat is in the water, have a planned haul out in March, and don't have a quick haul out option before that...

One manufacturer is stating that even a shaft modification might be required...

Searched for IP31s with any of the moving props, but can't find any references...

Of course, going with the OEM, and repitch to the 3YM vs the old 3GM is an option, but if making an investment, would rather enhance capabilities...

Any one out there? 

Add on, does anyone have their IP31 out of the water that could measure the distance from the end of the shaft (from the threads) to the rudder, and from the end of the keel to the rudder?
THX!!!