This rifle was given to me by Cpl. Vespers daughter some 30 years ago. Ser.No. 75857. He went to Cuba with Co'E' 2nd US Inf. I have lots of Provenance. No US on the  receiver above Springfield Armory. Stock and rear sight appear to be off of 1899 rifle, stock is smooth no markings. He left the Army as a Sgt. in 1904 & joined the Wisconsin Nat. Grd. but left in 1914 due to medical problems from Malaria he contracted in Cuba.