A well traveled SAA
This amazing early Colt Single Action Army, SN 5405, has an 1874 production date and “U.S.” stamps and a serious 7.5-inch barrel. The gun, likely an OWA (Orville Wood Ainsworth) proofed model, falls in the possible serial number range of Colts that were at the Battle of Little Bighorn, which is SN 4500 to 7527.
This makes sense as this gun is in the Canadian War Museum and was associated with Sitting Bull.
“Sitting Bull, a Lakota Sioux chief, and his followers came to Canada with this weapon after the 1876 battle of the Little Big Horn in the United States. The presence of these armed warriors worried the Canadian government. Officials feared that Canada’s western First Peoples would ally with Sitting Bull and use violence to disrupt settlement.”