'Donki' - The Kragyou are considering is a U.S. Magazine Rifle Model 1898 (Krag-Jorgesen).
It has the model 1901 rear-sight, which was the preferred sight for Krags remaining in U.S. Army service after 1905.
(It is likely that a lot of Krags that went to the State National Guard Units had the model 1902 rear-sight).
All the parts on this Krag are Model 1898 parts.
Even though the manufacture of 'head-less cocking-piece' was discontinued in 1900, the part was still acceptable and could be used during rebuilding of Krags.
U.S. Krag parts were not serial numbered or matched to the serial number of the Rifle's Receiver.
(Exception was some early model 1892 rifles, made in 1894, that had some parts numbered to the gun).
Springfield Armory was the sole manufacturer of parts and they were intended to be interchangeable, without hand-fitting.
(We learned this from the French)!
You are considering a very nice Krag. It may have even gotten to France with U.S. Engineers (???). It's probably impossible to know for sure, without documentation.
Attached photo of U.S. 12th Engineers in London during a 1917 parade.
Attachment 111326