Chris Hegar made a small run of them for the enduro clutch, about 10 sets 2 years ago. I had to wait about 6 months for them to get geared up to make them but he did get them made. I bought one set of them.
I have 2 New sets for the Horstman Sprint axle clutch for sale I got from Haddock. They are different than the enduro clutch.