The on-sale date is from the publication date recorded in the Catalog of Copyright Entries, Part 2, Periodicals, 1943, New Series, Vol. 38, No. 2.
Originally credited to Parkhurst, but this is Carlson, who is credited by Jerry Bails' Who's Who. He is best to spot by his horses with long, narrow tapering heads, and movement of frontlegs, either stretched out in front or lifted very high up under the chest. Parkhursts horses have heads with a marked convexed profile, just like a bull terrier. Carlson's horses can be found in most of the preceding Buck Jones stories, and also in his Rocky Lane stories.