Does kind of look like something that James Howe might have done. Lots of examples of his work in his Modern Gunsmithing books. He liked to incorporate stippling into his checkering designs and also used a lot of ivory.

If Harvey Rodgers ever did a checkering job like that, he'd have thrown it in the fireplace.

Whoever did it, it is a nice little rifle and I hope you and your grandson make some wonderful memories with.

John