I know that I was aware of the -gry puzzle by 1976 because, during the spring of that year, I clipped a newspaper advertisement solely because it contained the name Hungry Bungry. The version I remember was simple: "There are three words in English which end in -gry. What are they?"
Scheetz, George H.
"In Goodly Gree: With Goodwill,"
Word Ways: Vol. 22
, Article 2.
Available at: https://digitalcommons.butler.edu/wordways/vol22/iss4/2