I can't believe you can't find a 14.5 barrel... Those tend to be much easier to find since you have to have a permanently installed flash hider or comp installed for it to be legal without doing all the NFA stuff. Are you sure you're not looking for a 16" barrel? Also why are you set on 1/7? A 1/9 twist tends to not have as much throat erosion if you're looking for barrel life. It just won't stabilize the really heavy stuff but if you stick to the norm 55gr, 62gr a 1/9 will shoot just fine.

No such thing as Match chrome lined though. If you are looking for accuracy stainless is going to be the only way to go. If you are looking for a barrel to toss a lot of rounds down range with go chrome even though it won't be as accurate as the stainless.

Either way Bravo company has both stainless and chrome barrels in stock and BCM stuff is quality so you should have no worries.