Well, first off, it's either a Remmy or an Eddy, rxvr tells the tale. Bbl should match mfr and date of rxvr. Get back to me with rxvr mfr and s/n, along with markings near muzzle of bbl, and I can help you with this.
Eddys bring a lower price, ATBE, than Remmys or Winnys.
Just about all parts except springs are stamped with mfr ID letters, either E, R, or W. Some parts will interchange with P14 Brit rifles, those will be variously marked.
The rifle CAN be restored to "correct" by swapping/buying parts from Numrich. I've done it.
Unless you are VERY lucky, the front sight will be the incorrect height, as it will probably have been swapped for another during re-build. Brit Enfield sights will interchange. I MIGHT be able to help you with this, also.
$400 sounds a little high, but these are becoming scarce, esp in original mil condition. Sling pictured is incorrect for WWI.
Let me know if I can help.
FWIW, I consider the M1917 to be the BEST mil bolt-action rifle ever made.
If rxvr is Rem, rifle was made sometime prior to Nov 9, 1918.
Aug, 1918 cutoff= 352,199
Sept, 1918 " = 417,343
Oct, 1918 " = 475,370
Nov, 1918 " = 545,541
If rxvr is Eddy, rifle was made prior to May, 1918
Mar, 1918 cutoff= 354,351
Apr, 1918 " = 422,755
May, 1918 " = 510,263
Bbl and rxvr mfr should match, and dates should be within a few months of each other.
Original finish on Eddy should be blued (nearly black) Orig finish on Rem is prob blue, possibly transitioning to parkerized.
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