Bart comes in two bores 236 and 237 200 yards 3 shotsThey are all great barrels you can't go wrong with any of them but my personal choice would be the BART I like an odd number of lands as even lands oppose each other and are more intrusive on the bullet
Kreiger also makes a 236 or 237 I believe.They are all good. What bullet are you using that you need a 7 twist.? I would do one of the 7.5 twist. I have had no issues with any bullets in my 8 twist out to 1000 yards. 6 Creed will do 3175 with all the 105 and 107 bullets. 115 dtacs do just fine in my 8 twist too. So depending on the bullets you are using pick the right twist.
Shep