New York publisher Star Guidance published Texas Vengeance in 1951 as Star Books 22. In 1952 Harlequin Books brought out their edition in Canada under a different title, one of 85 changed titles published between 1949 and 1959. Gun Law's cover is from yet another Star Guidance book, Law of the '45, which was also published by Harlequin without changing the title and with an original cover.
Harlequin 172 - June 1952
Star Books 22 - 1951
Star Books 25 - 1951 (second printing)
Harlequin 128 - August 1951