What documents are you citing? Please supply the sources. Nothing credible has been produced and specific questions have been dodged. There are amateurs who claim to be more knowledgeable than either Brophy or Hatcher at every show and unfortunately, bogus snipers rifles have polluted the market. What I've read here wouldn't influence a 300 level history student at a small college. Let's begin with basic Springfieldology:
A NM 03A1 that left SA that way will have a small number in the feed lever recess on both the stock and receiver, such as a "2" for 1932. Also, the electric pencil numbers on the bolt will have a noticeably smaller first three digits and be neatly done. The configuration of the gas relief ports on the bolt is also important in determining originality. Bolt raceways will also have been polished and original barrels will have not only the star at the crown, but the star gauge number on the barrel. Original stocks were also cartouched and serial numbered to the receiver on NM rifles, not general issue. These are only starters.
1. In order to properly research this rifle, purchase or borrow a copy of Brophy's book and access his sources. It'll save a lot of reinventing the proverbial wheel.
2. Verify the serial number through SRS and if that fails, go directly to Springfield Armory records, find out when that serial number was shipped, to whom, and whether it was a general issue or NM rifle. This would establish if there is a USMC connection. There are grad students in the Springfield area who will do this research quite reasonably.
3. Contact the Marine Corps Museum at Quantico with the receiver number and check their records. These people are very helpful. There is a wealth of information on individuals, procedures, teams and units which they are happy to share.
I was able to trace the entire history of my NM from the day it was shipped until long after, and even the name of the purchaser when it left federal inventory.
There is nothing difficult in any of this and skilled researchers are usually all to willing to help. Without these basic facts, anything else is just hot air.
GOOD LUCK!