Strange that they would have Garands at Parris Island towards the end of 1941 and then be shipped off to the first large Pacific engagement (Guadalcanal) almost a year later with 1903's. Either the Brass preferred the 1903 over the Garandor the U.S. industrial base couldn't gear up fast enough to produce enough Garands for both the Army and the Marines.
Those guys had no clue that December 7 was just around the corner.