Dan Wilson,
Thanks for bird-dogging the serial number manufacturing dates here.

I have an Eddystone with a 1,345,XXX serial number and a 12/18 marked Eddy barrel.
According to oldguns.net U.S. MILITARY DATES OF MANUFACTURE U.S. Military Model 1917 Rifle: Eddystone:Covering numbers: 1 - 1355000
the date of manufacture for that serial number is January, 1919.

That date and the barrel date stamp seem to indicate the barrel and receiver are correct for each other. (All other parts on the rifle are Eddystone marked except for the cocking piece which is marked W NS.)

Does a 1,345,XXX serial number conform with a Jan 1919 manufacture date according to your sources?

Also, is it true that all late model Eddystones came off the assembly line Parkerized rather than with a blued finish?
Or was Parkerization done only when re-arsenalled?

Thanks you.