Lucas has been known to borrow from things, such as the source of my avatar, which is from an SF magazine cover printed in 1975.
http://binarybonsai.com/2010/09/18/george-lucas-stole-chewbacca-but-its-okay/
However, there were a lot of unauthorized Artoo clones doing promos at trade shows and even malls in the late 70's. Without more specifics on when the pics were taken, it's hard to say.