Uncle Mike's makes, or at least used to make, a sling swivel set.
Most of my TC barrels are 10" barrels, I most generally carry my scoped TC in the same Uncle Mike's bandolier holster I used for a scoped 7-1/2 barreled single action revolver.
I've done a couple of 14" barrels and two 16-1/4"ers. Rather than a holster, I used a long loop nylon web/belt, ran the loop between through the scope mount between scope and barrel, stuck the muzzle through the loop, then pulled it up tight. What's left went over my head and one shoulder and hung down on my left side with the muzzle to the rear. I always kept one hand on it just in case but it never offered to fall. Truth is, a long barreled contender is, IMHO at least, so clumsy the sling setup can't hardly make it worse. I do ok with the iron sighted 14" barrels, but with a scope I want short, 12 is eh, so-so, 10 is better.
