Looking at the cowboy range I'm a little surprised there are no really iconic figures included.
"Man with no name" ("for a few dollars" more outfit). Poncho thrown back over his left shoulder, sheepskin vest and shooting from the hip.
Col Mortimer -with his shoulder-stocked revolver
Tuco -as he was in the final gunfight, with the distinctive way he carried his gun and his "what's going on???" experession
El Indio -holding the pocket watch.
Nino -the really big bear like mexican who was Indio's lt.
Wild (the hunchback)
Bret Maverick (James Garnier, of course)
Wild Bill Hickock -gun butts angles forward, big knife on his belt -look for the actual pictures of him.