Is This Legal?

[Heinz]

The list I posted exempts those firearms from the National Firearms Act; You can attach the stock. There is no prohibition on owning stocks and not attaching them. You will note in the list I posted:
"Luger, DWM, original models 1904, 1906, 1908, 1914, and 1920, Naval pistols, cal.’s 9mm Parabellum or 7.65mm, in both the Commercial and Naval military varieties; in both altered and unaltered barrel lengths in the Model 1904 and in both altered and unaltered safety markings in the Model 1906; with original board-type detachable shoulder stocks bearing brass or iron discs, with or without markings, or, if without brass or iron discs, being of the Navy flat board-type. This exemption applies only to the listed Naval Luger pistols if mated to the Naval Luger stock and will not apply if the Naval Luger pistol is mated to the Artillery stock. The Naval stock has an overall dimension of 12-3/4", a rear width of 4-5/8", a front width of 1-1/2", a rear thickness of 9/16", and a front thickness of l-3/16"." This section talks about "mating" the stock to the gun.