The Gunbelt worn by Marshal Caleb is actually a Swedish army belt named "ammunitionsgördel m/1900-12" it's actually from the 20th century and therefore does not fit the time period of the series.
The fixed-blade knife shown in the intro with the marking "24X" on the ricasso was a Solingen Wildcat, which was not manufactured until the late 1950's.
Kat is supposed to be a fugitive after killing a man at Batoche, which was not founded until 1872 - Métis (and white) settlers moved to the area in the aftermath of the events at Red River and Louis Riel fleeing south in 1869, the supposed year this story is set in.