Blue Point did sell a cart that is nearly identical to the HF 4 drawer, with a few bolt on mods and shocks instead of hinges. That key in the first and third pictures is a Blue Point key (I put a Blue Point lock into my HF 4 drawer, as well as the lid handle and other mods).
Betting it is a BP box (worked with a guy with a yellow one), but no reason to buy one when there is next to no difference next to a HF model.