In the 1970s, there were a plethora of short-lived fan/pro zines...
...that up-and-coming artists contributed material to for free in order to get their work brought to the attention of magazine and comic art directors, and already-published pros used to promote their own non-DC/Marvel projects.
It was like DeviantArt, but in print.
Imagination Publications' one-shot Imagination (1971) was one such zine.
Besides this Jeff Jones short, there was a cover and frontspiece by Gray Morrow and tales by Berni Wrightson, Mike Kaluta, and Neal Adams (who was promoting his own potential syndicated strip, Tangent.)