You can use the bolt from your rifle with the new barrel. The barrels are pre headspaced along with the bolts that have a min/max tolerance for interchangeably while maintaining proper headspace. The bolt does not need to be "matched" to the NATO Spec chamber. The G.I. Tech Manuals warn against interchanging bolts as a rifles returned to the Armory Depot as they may have many tens of thousands of rounds fired through them and a worn bolt or barrel extension may be out of the min/max tolerances. If there is any doubt they can be checked with a NATO Spec "NO-GO" headspace gauge. If the bolt does not close on that gauge headspace is alright. Signs of excess headspace would be flattening of primers, split necks or separated cased of fired rounds.
We recommend replacing gas rings and extractor spring if 3,000 rounds or more have been fired with the bolt to be used to break in a new barrel.