I have at least one unmarked Gray wrench. It looks exactly like all my other 70's gray wrenches, only there is no name printed on it. All it has is "3112B" (the Gray part number) and "Canada" stamped near the open end.
I also have some Dreadnaught, a several old Gray wrenchs, and these Dubl-hex don't look anything like them. Old Gray stuff feels "chunky" with thick handles and lots of meat around the ends. Besides the fact I've never seen a Gray wrench with that "lowered panel" design, IMO those Dubl-Hex are too thin and too light to have come out of the same factory.
Roger