Greetings,
Does the box have any Plomb or Proto markings on it anywhere? I cannot perceive from the pictured whether it meets the build specs listed in the Plomb/Proto catalogs. I know that Pressteel manufactured and sold boxes under their own name. They usually stamped of painted their name on the second drawer right where the brass plate is riveted ( or is the brass plate a Plomb produced name tag?). So it could be a pressteel branded box finished in red or a Plomb/Proto.
Thanks, StevenF