I recently picked up a 10" 357max Contender barrel from an older gentleman who is beginning to divest a lot of his collection, and he gave me about 300 rounds of cases and maybe a couple hundred that were loaded and ready to go.
I paid $175 for it all, but most Contender barrels in good condition go for around $200 these days. Stainless and less common calibers can run more. The .22 Match barrels can run a little more as well.
GB often has a couple hundred TC barrels for sale and you can usually find any caliber you want. Many go unsold at the $200 mark, so if you are patient, you can do ok on pricing.
I just checked now and there are a couple .357 Max TC barrels being offered at this time.
Here's one interesting 357max barrel, interesting because it has a peep sight mounted on it. I just thought it was interesting because of the sight, although I myself wouldn't be interested in owning it (I ONLY buy 10" barrels, period.)
Thompson center arms contender super14 357 Rem max : Pistol Barrels at GunBroker.com
And here's a 10" with no sights:
T/C Contender 10' Bull Barrel in 357 Maximum : Pistol Barrels at GunBroker.com
One thing about Contender barrels you see for sale; a LOT of them are being offered without the rear sites because they had been scoped at some point. However, those rear sights are worth at least $30 or more, so whenever I shop for Contender barrels to add to my collection, I NEVER EVEN CONSIDER a used barrel unless it is complete with rear sights.
If you have absolutely no interest in ever shooting non-scoped, then by all means buy a bare barrel. Just know that there are different sights for different barrels so when it comes time to sell the barrel, you would be able to sell it easier if you could re-install the
original rear open sight.
I think I've pretty much run out of TC barrels I need since the I have no interest at all in the calibers that I don't have. Now I'm working on making custom display boxes for each of the three Contender frames I have with their respective associated barrels (Stainless, AA, and a Blue).
Bottom line is that if you are patient and wait for the exact configuration you are looking for, it WILL show up eventually. When it does, just be willing to spend a few dollars more for it. Don't let the one that you really want get away from you, and, don't settle for a so-so barrel if it's not what you really want in caliber, length, material, and being complete.
If you are a "collector", then you might hold out for one with a box, but that has never been something I wait for if the barrel looks really good.
At the same time, probably half of the ones I've bought over time did come with original boxes, a nice plus for when I have to start divesting my own collection due to my own age considerations (probably in 5 to 10 years).