The bars are too narrow and manifold for a COE grille.
My money would be on it being a modified '39 DeLuxe grille. I'm not sure if the '40 Standard grille is identical to a '39 DeLuxe or not. Of course, I've always been easy money in anything gambling, so take my opinion for what it's worth.
No way there's any kind of "military" secrets involved with that concoction. I'm with skidmarks ..........that's some kind of repro unit that's been "slightly-gomezed". DD