It looks like the Swagelok tube benders are the way to go for stainless from reading various forums. Except they don't make a 3/16" version. It appears the 600 series Ridgid benders are basically knockoffs and they have a 3/16" version. That's model 603. The 1/4" version is model 604. They're made in China, so I thought I'd check AliExpress. They're on there. Reviewers say they're the real thing, but even if they're a knockoff of the knockoff I guess that's not so bad. Test Equipment Depot in the US has them for a little more.
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