The clip has a vertical "DIAMOND" inscription and also "PATD" inscribed along the top arch of the clip, in tiny letters. It seems more of a deco-style clip, than a WWII style.
The top screws off to provide access to an eraser. This is an unusual feature for a nosedrive pencil. Spare leads could be stored in the barrel. This one still had two leads, 0.9 mm, dating the lead size to after 1938.