A star gauged barrel also has a star gauge number on the top of the barrel under the handguard. A star gauge barrel could have been put on any M1903 rifle, but one needs to be careful (and also know what the mark looks like) about paying a premium for a rifle with such a barrel or for the barrel itself. As an example, some folks have ground the end of a Torx wrench sharp, and used it to put on "star gauge" marks. They look nothing like a real mark, but some folks have been taken for hundreds of dollars.
Jim