Looking for it. Octura quit making them for a while but started again. The guy that I buy all of my Octura parts from called me asking if I had a spare!
ProBoat had one for their Miss Bud boats but I don't know if you can get those anymore either.
OK, seeing how I don't have any fancy tools in the dungeon like a lathe I just chucked up a drill bit into a drill that fit the collet and while running, took a hacksaw blade to it. Sure, it was crude but it worked. You'll see that the shoulder will have to be cut off behnd the hex.