Magnum Machine has been shooting 338LMimp for many years.
They claim >20-25 reloads of brass.
AFAIK they have Redding bushing dies, and reamers, and suspect they would re-chamber an existing rifle or build one using a custom their own ATRS action.
https://albertatacticalrifle.com/hik...verick-actions
Good Luck, YMMV.