GOOD NEWS. . . . The PICTURE UPLOAD FUNCTION IS WORKING !!! The tech folks at the parent company have been able to remedy the issue. You can upload pictures once again. Thank you for your patience.
More to the point what application do you need the prop for.
A 13" pitch is for a 13 to 15ft relatively light runabout.
Are you needing to improve performance?
What is the present max rpm and speed and prop size?
You obviously did not check right here on IBoats. After all, they do sponsor this forum and they do have virtually everything you need for a boat. Check below.