It certainly seems intriguing that none of those other 8 books have been reported or uploaded to TuckDB as having a board binding. Perhaps whoever wrote the copy for that Arbuckle Coffee premium list was mistaken, or perhaps so few of those were ordered that they’re very scarce 125 years later. I suppose that unless one shows up in its original mailing envelope or box, as happens from time to time like it did with my Young Folks Painting Book acquisition, it will remain a mystery!