Sabre went out of business a few years ago and most folks don't remember them at all. Their barrels were expensive, they made their own, and the one's that I have are great (possibly exceptional) shooters. Bravo Co also sells barrels in 410SS. I've got 3 of the 16" fluted mid length barrels and bought them all new from individuals. They originally were $400 or so but don't seem to be valued anymore as Sabre is all but forgotten. Rest assured it'll be a quality barrel. You might get it pretty cheap just because there are so many barrels available now. If you like the length and profile I'd offer no more than $200. A 24" isn't everyone's cup of tea and again, many don't know how good a barrel Sabre made.
As an aside they made 50 BMG barrels under contract for the military.
