I buy all my CA-400 size tool holder blocks from Jeff at Tools4Cheap.net because they're only a couple of dollars more than Shars of CDCO, better quality and he's a great guy. Darren (Mayhem) and I have met him and he's really worth giving him the business.
As for the two-roll knurlers, I have one made by Dorian. It takes a LOT of pressure to get a good knurl from it, so I'm thinking of making my own that would have opposing knurl rolls. The one in our "Projects" section is good, though I want one that has up-down travel on the adjusters as that's the way a good one I used to use at one of my previous jobs worked.
As for the two-roll knurlers, I have one made by Dorian. It takes a LOT of pressure to get a good knurl from it, so I'm thinking of making my own that would have opposing knurl rolls. The one in our "Projects" section is good, though I want one that has up-down travel on the adjusters as that's the way a good one I used to use at one of my previous jobs worked.