Here is a one page story by Henry Boltinoff, from that same issue #155 of House of Mystery. The gag isn't very clever or funny. The cartoon gives a further example of the popularity of those monster model kits from Aurora. Aurora must have been an important advertising client for DC, for them to put a free blurb about Aurora's series of monster models into this filler piece. I wonder what the story, behind the scenes, of this cartoon's creation really was.
art @ DC Comics