Prop size for 230 with '96 225 yammy

[1988Mako230]

I am hitting 5000 with current prop. Top end seems light. Boat is not slow out of the hole. Top end fades as throttle moves the last few degrees forward. Yesterday on calm water I hit 33-34 knots GPS. In a past reading when the chartplotter was set to mph it hit just over 40mph. I had a full tank of fuel. I was the only person onboard. Small cooler with lunch so no extra weight.

I think 5k is max rpm for this engine. Even though it is reaching 5k just as it comes to full throttle, the prop does not feel right to me. Thoughts? Suggestions? I'm hoping to hear from someone who has this boat/engine combo. In 09 there was an owner of this same set up but he's long gone and the site does not have his email. Thanks.

[1988Mako230]

My guess is it is a 15-17. 15" diameter, 17 pitch. The -1 may be the cup with a -2 and -3 having more cup. Pic make it look like 7" was the measurement. It measured 7.5" from center shaft to outside of the blade.