"Is it correct and is it worth $450.00?"
Don't worry. In a few years time you will laugh about that.
The slightly shot-blasted surface of the barrel and the RIA stock mark, make me think that it is an arsenal rebuild. If so, you can expect that, although the rifle does not have the "all-matching" Remington, Eddystone or Winchester markings so beloved by collectors, it is very likely a better shooter than most of the all-matching originals from WW1.
I thoroughly recommend that you get the book "United StatesRifle Model of 1917" by C.S. Ferris, ISBN 1-888722-14-2, which actually shows, on the cover, a Winchester receiver close in date to yours. On P. 180 there is a table that dates the receiver 191425 as the last made on 25 Feb 1918. So the one you are looking at would have been made on the same day.
Oh dear! I just noticed that you wrote "This will possibly be my 1st M1917." So it is not yet yours!! What are you hanging around for? Get out and buy it now!
Patrick