SInce you have a low pitch prop already, your only other real option besides the high 17pitch wyou also have is the 15.5. I'm presuming the 14pitch gets you a little over 40mph in your boat, then you'll get about half the benefit of top end and half the benefit out of the hole, maybe more, the 17 pitch OEM is pretty turdly out of the hole.
'06 X2 MCX
"I understand why some people may not want to do this the way I have recommended but I can't understand the death grip some people have on a toilet plunger with a hose fitting." -JimN