Brian, no, equaling files are normal straight flat files with teeth on all four sides I think. I looked in the catalog and online at MSC and couldn't find checkering files. The closest I found were called "Bodifiles" but they were for body work and looked much different than what you want.
The files from Brownells are top shelf aand outrageously priced. Hold onto your shorts! That's what I've always bought, but they were $29 then.
If you haven't used one before, I'd suggest don't bear down too hard. Teeth break.
Edited to add: Sheffield has Grobets in 20, 30, 40 tpi for $25.50. Page 40 in their online catalog.