MRAD SMR barrel replacement?

That's precisely why I didn't take my buddy up on his offer to sell me his 300NM SMR.

It is stupidly accurate, but I didn't want to have to deal with the inevitable barrel swap. I'm guessing that it would have to go back to Barrett. There is so little information out there available on this though.
 
Barrett SMR diagram

If not for the press fitting, a barrel change would be very straightforward with the right wrench.

edited to add I went down this road several years ago and, no surprise, a company as big as Barrett was unable to accommodate any chamberings or barrel lengths that weren’t already standard offerings from them.

How willing were they to take rifle in and swap barrels?