Is several parts to that - some may not care, some do.
First part of WWI had three makers in USA making P14 for Great Britain - the rifles were never made before or after, or anywhere else. So original stocks will have cartouche and other markings to indicate made by Eddystone (E), Winchester (W) or Remington (R) - they are slightly different from each other, besides the markings. And they look similar, and can be made to work for either, but P14 stocks are different from E, W and R stocks made later for M1917 rifles. Then the two hand guards - should have been marked inside who made them - so three original matching pieces, or some random pieces that "fit"? Then was big undertaking during WWII by British to rebuild their WWI P14's - so there is also made-in-Britain "original" stocks - different than the WWI ones made in USA. So, what you have, what you can identify, what a buyer can identify all mixed up together. And whether still straight or now warped. I have one here in a Numrich reproduction stock - looks good, but not in any way "authentic". When I ordered P14 rear hand guards from Numrich, I received M1917 hand guards - slightly different, but "fit" and "work". Numrich agreed - say that they searched their warehouse - all that is in their bins for M1917 and for P14 hand guards are the same - all are for M1917. As mentioned - some might care about stuff like that - others may not.