Remember though that turning the basic pin is easy, anybody with a lathe can do that. The rounded knurl however will be impossible without a special knurling tool which would have been made by the factory specifically for that pin head size. You could just use a diamond knurl which is what most replacement pins have.
But the real tricky part is the spring which is small, awkward to hold without special jigs, must be hardened and tempered and a attached with a small pin.

This is why the guy in Austria that makes them, sells them at a fairly high price which in my view is completely justified.

Matt.