Interesting, I have never seen one like it either. Given that Star shipped many of their Damascened or engraved pistols in leather cases, maybe that box was intended to be a shipping box to protect the leather case and its contents while being shipped to the customer ?
Also check the Star book, page 463. It shows a .22 conversion kit for a Super A pistol in a particle board box that looks like it has the same style sliding lid with finger hole.