I just ran across this today in my CNC router browsing. I had never seen these and remembered the insert tooling for lathes some were trying to make. Here is insert tooling specifically for wood and maybe some of the inserts could be useful for some homemade tooling.
When I look at the inserts it gives a list price then says Free so I assume I am seeing something wrong because that can't give away all the replacement inserts..
But for what its worth here is the home page...
And the insert tooling
And the inserts themselves