| Its basically an 8mm pin punch with a 'v' shaped 4mm groove cut down the middle.
I did a search around t'internet and found some fancy Motion Pro tools but they seemed a lot of money for summat I would use once a blue moon.Then I found a pic on the U.S Tsubaki website of the punch and just copied that.
BTW,B&C say you can just peen the pins over with a ballpein hammer.(Using another hammer behind the link as an anvil) | 
Hybrid Mode
