I have a Michigan folding prop for sale that came off of USA139. I bought the boat and it had an extra. I surveyor estimated the value to be $500-$600.
Stampings: Pat. 3.715.171 16 x 9p on the blade inlet (16" diameter and a pitch of 9)
The initial inside diameter is 1" standard SAE bore but the inside reduces to .75" to fit the shaft size.
I am asking $300 so I can quickly sell it to buy some new spin blocks! My computer is having issues uploading the image, but if you are interested email me for pictures brettlangolf@gmail.com