Sorry it took a bit, but here is one of the boxes I made for a friend of my wife, who's dad passed earlier this year. He served in the Navy aboard ship. I had HER choose the challenge coins, have the engraved plate made, (in advance) and decide on the final layout after I offered her several options. Concealed in the space behind the coins and name plate are several small personal items of her dad's that she wanted to keep, but didn't need to handle again.
The box is solid mahogany, and finished in Watco Oil with several coats of bees wax, which she can rewax and buff out for that soft sheen if it dulls.
This is another original design, which I have used for several boxes for Veteran's: myself and my son in law included. You can add a challenge coin or cover emblem to the front of the box, display medals and insignia in half the box and the flag in the other, and use uniform jacket material or silk, velvet, or whatever the family chooses for the background.
My box was made from a slab of black walnut firewood. I tossed it aside to dry when I saw the grain.
My son in law's box was made from a select piece of curly cherry, as a retirement gift.