Forty years later, I finally have the answer. The fact that this is a topic that has remained on the fringes of my consciousness for so long speaks volumes about my neurosis. But thanks to the World Wide Web (as it's called), someone finally addressed this issue.
In 1969, I purchased this one-shot Gold Key comic:
I noticed in the publisher information that it was created by "Total Television" which were the cartoon producers behind "Underdog", "Tennessee Tuxedo", and "Go Go Gophers". They were animated by Gamma Studios, a cartoon factory in Mexico that was contracted to make cartoons for General Mills cereal ads. And this place also animated the Jay Ward cartoons: "Bullwinkle and Rocky" and "George of the Jungle". Many people are confused by this, thinking that these were all made by the same creative teams. They just looked alike.
Anyway, I never saw an animated version of this. Or even heard or read of one.
So two years later, on Saturday morning on NBC, we have "The Roman Holidays", a Hanna-Barbera sitcom with similar characters (and even a lion). I bought the first issue of that comic book.
But thanks to Scott Shaw's blog, based on information from Mark Arnold's book, we have an answer. I am grateful, that I am not the only uber-geek over forty who obsessed over this.
So buy Mark's book. Support my fellow cartoon geeks.