As others have stated, it's best to look into a used stock, or a cut-down stock that can be repaired.  Boyd's used to have Krag replacement stocks... but they were very poorly cut and inletted... and required a great deal of work to fit properly.  The CMP offers replacement stocks for 1903 and Garand rifles.  I sure wish they offered Krag stocks too....

As for the barrel, Criterion sells Krag barrels through the CMP, and the CMP gunsmithing service will even install it correctly for you!