A851 - 5mm x 15mm Brass Pin Hinge
Probably the simplest hinges to install. Drill 5mm holes in your box lid and case, put a 45° chamfer on each part, put glue in each hole, insert the hinges, open the lid once to orient the hinge, and then close the box until the glue dries. You have inconspicuous hinges with a built-in 90° stop. Solid brass. Sizes given are diameter by overall length.