I’m also looking for a SS prop for a Nav175 with 115 Yamaha. Currently 19P aluminum run 6100 RPM at 42 MPH. I contacted Powertech and they recommended a 4 blade prop part# YM90SCD4R17P, but I think I will eventually go with the one Propmann recommended.
NORD I think you can order the props from propman at http://www.brainerdprops.com How do you like you setup so far?