Prop recommendation needed

[Little orange buddy]

Howdy,

Looking for a recommendation, need to re-prop my GT140.

Original merc 402 suffered an epic failure last fall, I purchased a super clean 2000 Yamaha 40hp 2 stroke. Motor came off a pontoon and was propped accordingly for that. It's flat as a board.

Looking for recommendations on diameter and pitch. It's clearly not a high speed rig, but I'd like to get more speed and faster to plane than it currently gets me.

Opinions welcome!

Thanks.

[Hyperacme]

Yamaha 40 / 50 HP owners manual
http://www.yamaha-motor.com/assets/service/manuals/1/LIT-18626-06-58_1385.pdf

Yamaha prop selector
http://www.yamahapropselector.com/propSelector/web/

Yamaha Prop Shop Library
http://yamahaoutboards.com/propellers/prop-shop-library

Yamaha prop page
http://yamahaoutboards.com/propellers/overview?gclid=CJHE0ZWl7NQCFQOMaQodoSsK8w

Glastron GT140 = 510 lbs.
Yamaha 40 HP = 200 lbs.
Battery = 40 lbs.
6 Gal. gas and tank = 40 lbs.
Total is about 800 lbs. before you and any other stuff you add.

[Plugcheck]

Ask around at different marine parts outlets, many will let you test props.  Omaha marine does that here, you buy one, try it, and if it still looks new, you can trade it for a different one.  Took several tries on my pontoon.