Probably from Jim Garrard

He seems to have most of the scarce chips I don't have. However, I don't remember for certain. He frequently sells on eBay as well as attending the Club Conventions.

It's my guess that Hex Nut design is just a geometrical design and doesn't necessarily represent a 3-dimensional fastener. Dale has it in Designs category, not Misc (but he did name it Hex Nut [g]).