Hi RTL
In one of the early pictures I belief that I can read the S/N as 1511565-FWIW.
I believe that it is an assembled rifle because"
1. The cocking piece is 03A3
2. The Bolt Sleeve is Smith-Corona
3. The butt plate has the fine checkering lime pre-WWI ; not the coarse checkering of the NM. I bought a couple of thee in the 1960's for $5.00 each
4. The parkerising looks to be like that gray that that is common to parts that I ordered through the DCM in the 1960's -particularly the trigger guard.
FWIW