Lock type for a door on a large box
Right Angle Hasp



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This type of right angle hasp would negate the need for guide pins, but would be inside the box.



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Flexible Hinge Hasp



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My first idea, before I thought of those hasps.

Barrel locks on the inside that are thrown into holes that are drilled into the sides (shown in green on the left). 

And doll rods or guide pins to prevent side-to-side movement (shown in green on the right).