i understand, as i couldnt tell from the pic if it was the integrally machined one DSA uses on the sa58's, or an externally attached brake. im assuming the brake is a US part, because with its addition you do need that seventh part. most brakes are welded or silver soldered, but they still count as a part requiring a seventh us made part, the same as AK's with a brake needing 6 parts instead of 5 without one. it is a "muzzle device" as listed in the list you provided, regardless if its a brake or FH, perm attatched or not. the only way it wouldnt be is if its integrally machined into the barrel, as i thought you meant.
fwiw, you did highlight it in the US parts list you posted, so thats why i said even if it isnt internally machined then its still us made and counts as the seventh part.
i apologize to everyone if this post unneccessarily bumped the ad.