On NC-331 we have used mostly two different feathering propellers, Max-Prop and Flexofold, both as three blade versions.
Max-Prop is the Classic three blades version, link below:
http://www.maxprop.it/site/productShow.php?lang=en&idm=3&ids=1&id=2
and Flexofold:
http://www.flexofold.com/3-blade-folding-propeller/
Those both work fine, but Max-Prop is the one we have used much more.
In case you need more information, please let me know.
best regards
NAUTICAT YACHTS OY
Veli Kärjä