Best place to buy a krieger barrel?

[Eye_guy]

I own several grendels already, all set up for hunting. Thinking about getting a range toy, meaning weight isn’t a huge issue. I’d like to build a tack driver, my local range goes to 600 yards so looking to hit good groups to that distance. Started buying some odds and ends parts as they go on sale. Full disclosure, I’m not 100% decided if I’m going to go 6.5 Grendel or 5.56. In either event, I’m thinking of getting a krieger barrel. A couple questions are:

What barrel/length/profile would you recommend for 5.56 or Grendel?

I don’t see a reason to not do a matched bolt, but interested in thoughts there as well.

Who would you order from?