GUN: Showdown - PSP - #19. Clay Captured, Take Down Hoodoo [1/2] - YouTube
Gun: Showdown for the PlayStation Portable (PSP) Gameplay Sample - YouTube
Gun Showdown Review - GameSpot
Gun Showdown Sony PSP Gameplay - Multiplayer Showdown - YouTube
Gun Showdown on PSP came out 4 years before RDR1, and it also nails the cowboy vibe, with such a small open world and janky controls. : r/reddeadredemption