Any 1915 is a scarce piece.
For one thing, they only had 2 factories at the time and production still was ramping up.
Need 3 more reasons? How about these: 1916, 1917, 1918. ALL were very hard on rifles. VERY hard on rifles.
As built, it would have had volley sights front and rear, magazine cutoff and the rear sight should be adjustable for drift (which people insist on calling "windage"). At the very least, it should still have the SLOT for the Magazine Cutoff.
Spend some $$ now, start looking for parts and, year or so, you could have an issue-condition 1915 battle rifle, which is a darned scarce piece today, 99 years after they were made.
In the meantime, you have the single most reliable freezer-filler ever built.
GO BUY THE THING!!!!!!
Then bring it here and let us drool at it with you!