This issue is a variant of Marvel Tales (Marvel, 1966 series) #174 [Direct]. There exist further variants.
Per Nick Caputo: "Spider-Man figure is by Kirby, probably inked by Brodsky. I spoke to John Romita and he recalls being in the office when Kirby was correcting the cover. It was changed because Spider-Man's backside was facing the reader".
Ditko's unaltered version of the cover has been published in various reprint editions and foreign covers such as this one: http://www.comics.org/issue/412129/#1026053
Reprints original letters from Amazing Spider-Man. Includes an editorial by Danny Fingeroth.