Rhinestone setting tool question

I'm planning to add rimset rhinestones to a blouse I am making. I ordered and received a tool called Brisk-set nailhead/rim-setter, model #40N, along with some size 20 rimsets. What the site did not tell me was that an adapter is needed to set the #20 rhinestones I am using. The site apparently does not sell the adapters. Can someone tell me a place where I can purchase this adapter so I can use the tool? Cheryl