T/C used to offer a "swap barrel" ML called the System One? Rem700MLs can be barreled but it requires a few tools and some skill. They had 45, 50 and 54cal barrels. The Savage is somewhat easy to swap barrels with the barrel nut wrench and you can buy barrels for about $300.

On my Knights i can just swap out the barreled action with triggers but there is not much of a savings.

The new ML only T/C Pro Hunter would be a good platform for a easier swap barrel but no one makes any barrels for them yet other than the factory 50cal.