I didn't find anything to strip my coax, so I made a fixture for my dremel tool. See pictures. I used the plastic routing attachment that came with the tool and screwed on an aluminum assembly that supports the coax as I twist it. Also shown is the resulting stripped coax. It needs a little deburring with a needle file, but the result is pretty good. It takes a few practice cuts to get the depth set right.
Pro tip: don't bend your coax before stripping it.