help with prop size(pics)

[tjl76evinrude]

im trying to get rid of some vibrations and want a new prop since mine is beat and im looking for some help. on iboats its only offered in 9", 10" and 11" pitch. im hoping someone here can eyeball it and give me a good answer on the pitch.

its on a 1976 evinrude 25 hp.
the smaller pitched prop in the pics is my spare. back when the boat was my grandpa's it was spinning in the hub. one of his friends drilled it, tapped it and put bolts in it. pretty crummy fix but it worked i guess.

anyways i want to get the same or slightly smaller prop as the larger pitched one.

 

[Silvertip]

Re: help with prop size(pics)

You can measure diameter but you cannot determine pitch with a ruler. A prop shop can put it on a pitch block to tell you what you have.