Some information on this issue supplied by Tom Lammers and the Atlas Timely discussion list.
from The Ringo Kid Western (Marvel, 1954 series) #8 (October 1955) [as "The Changing West"]
in The Mighty Marvel Western (Marvel, 1968 series) #36 (December 1974)
in Capitaine America (Editions Héritage, 1970 series) #48 ([Août 1975])
in The Mighty Marvel Western (Marvel, 1968 series) #38 (April 1975)
in L' Incroyable Hulk (Editions Héritage, 1968 series) #49 ([Août 1975])
in The Mighty Marvel Western (Marvel, 1968 series) #38 (April 1975)Border art by Joe Maneely.
in The Mighty Marvel Western (Marvel, 1968 series) #37 (February 1975)
from The Ringo Kid Western (Marvel, 1954 series) #6 (June 1955) [original title "The Iron Horse"]Text story with illustration.
in The Mighty Marvel Western (Marvel, 1968 series) #36 (December 1974)
in The Mighty Marvel Western (Marvel, 1968 series) #36 (December 1974)
in Capitaine America (Editions Héritage, 1970 series) #48 ([Août 1975])
in The Mighty Marvel Western (Marvel, 1968 series) #38 (April 1975)