I needed locker hinges for my Nc39 back in 2012 and conducted a similar wide search as Sam did. Eventually I bit the bullet and got the spare hinges from Nauticat themselves. Expensive, but needs must!
However, later on I did find that a company called Schwepper, http://www.schwepper.com who sell similar ones to those on my Nc39 locker doors. Look in Chaper/Section 5 of their on-line catalogue. I have no idea of the cost or availability. They have a wide selection.