The hammer on the left is a Boogie Stroke hammer. It will fit a Vaquero or Blackhawk. Vaquero and Blackhawk hammers are basically the same. The hammer in the middle is a stock New Vaquero hammer. The hammer on the right is a Super Black Hawk hammer that has been modified to have a half-cock notch. The primary purpose of the photo was to show the differences in the spur shapes.
Thanks again, Pettifogger!