The on-sale date is from the publication date recorded in the Catalog of Copyright Entries, Part 2, Periodicals, 1945, New Series, Vol. 40, No. 4.
Vincent Fago mentions this cover at http://twomorrows.com/alterego/articles/11fago.html (excerpt from Alter Ego, Vol. 3 #11) and states that he usually inked his own work unless his brother Al Fago was available.