The on-sale date is from the publication date recorded in the Catalog of Copyright Entries, Part 2, Periodicals, 1942, New Series, Vol. 37, No. 2.
Saltarella, via the GCD Error Tracker (http://errors.comics.org/show_bug.cgi?id=8165), notes that the cover artwork greatly resembles the artwork in the story with the same character that is signed by Elkan.
Credits suggested by Jerry Bails Who's Who.