I haven’t cracked my copy of Western City for a while and it’s in storage now, but it seems a good fit for a narrative game exploring the classic themes of Westerns. Or running Support Your Local Gunslinger, whatever you’d prefer.
Frontier Scum is decidedly not in the realm of Western cinema the OP is referring to. It is an interesting game, though, as a self-described “Acid Western”. More like a Wild West game dropped into a degenerate Yellow Submarine or a Mœbius comic strip. Much heavier on the surreal than say, 3:10 to Yuma.Two suggestions come immediately to mind; they're both pretty different:
Tales of the Old West (Year Zero Engine)
Frontier Scum (Borg inspired)
Is there a system that can actually reproduce the movies of Peckinpah and John Ford? If so which one is it?

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.