The M14 #1 is in the possession of the national Parks service.
Springfield Armory NHS, US NPS
Eisenhower M14 Cat.# SPAR 1508
The Army customarily gave each new United StatesPresident a special rifle made at Springfield Armory. Before presentation these pieces were given a detailed examination which often revealed flaws. Consequently, when the Armory was requested to build a presentation M14 for President Eisenhower, it was decided to make two rifles. The first was found to be flawed. Examination of the second M14, however, revealed no flaws and it was selected to be presented to the chief executive. M14 serial D.D.E. #1 is displayed here. The rifle given to President Dwight D. Eisenhower was D.D.E. #2.
I would guess that #2 is in the presidential library