I don't believe Briley will install tubes in pattern welded barrels, but sent an email asking.

I vaguely recall back in 2008 when Vic Venters reported on Greener's manufacture of new doubles with vintage damascus tubes, a comment possibly by David Dryhurst that there was some challenge cutting the chokes? that the barrel would not cut smoothly but would chip/fragment? Does anyone else remember?

https://sites.google.com/a/damascusknowledge.com/www/home