Nice article! (I checked the link, and they really did put "hawk" in the original title, instead of "hock"!)
I've heard people use the term "hawk" to describe a sale, but I think you're right. He didn't sell his rifle, he effectively traded it.
I was reading American Rifleman the other day and they had a photo of a bunch of kids holding rifles and that picture was taken in 1929. From then until not too many years ago it was normal to see kids with rifles or shotguns. Real or fake.
Can you imagine the horror if the story about an eight year old trading in his rifle for a washing machine were to happen today?
They'd ban the kid from school forever and have his grandma in jail for one reason or another.