I'm assuming we're talking a sporter, cause blanks from the barrel makers that will finish out at 30" are expensive. That would make the Criterion more attractive, if we were talking full length. There's enough meat in a Remington 700 .308 barrel that the chamber could be removed, and the square threads cut by someone who knows how. Finished diameter would be about the the same at the receiver as the standard barrel. Extractor groove would have to be cut, and the 30-40 chamber cut. I know the 700 barrels will work cause I got one in .243 that I'm going to make a 6mm/30-40AI out of someday. I did enough measuring that I'm fairly certain it'll work. Too bad I moved, long drive to the fellow I found that cuts square threads. About any take off barrel could be made to work by a good gunsmith. At one time I had a heavy Obermeyer barrel all done up for my previously mentioned wildcat project, but decided to make a 6x45 AR upper with it instead. You can find some good takeoff barrels on gunbroker, found my Obermeyer there for $10. Opt for insurance, I received an empty box that I paid $70 for and the seller wouldn't take responsibility for his poor packing. He left it free to go to and fro a couple inches and it punched its way out of the box. It's been a couple years, the barrel never did show up. 03 and 03A3 barrels will work, most 03A3 barrels are two groove. I don't think I'd care to mess with 1917 barrels as the originals are more .303 dimensions, but WWII era rebuilds have US dimensioned barrels made by High Standard and Johnson. I don't know how they'd finish out.
"I have sworn upon the Altar of God, eternity hostility upon all forms of tyranny over the minds of man." - Thomas Jefferson