1972 Double-Headed Kennedy Half

For a DIY'er this would simply be a good challenge.

If I was interested in doing it, I might try by drilling a hole in a piece of hardwood (better soft aluminum) to half-of-half dollar depth, put strong adhesive in the hole, insert a half and allow glue to thoroughly dry.

Hold the block coin-side down on a (mounted - would not try it with a handheld) belt sander and sand away until no coin is sticking out of the hole.

Apply solvent, remove half-of-half dollar, repeat with another block and half dollar.

Combine two halves-of-halves with glue.

Problems I foresee are keeping the block as level as I would desire while sanding. To which I would then devise some sort of shims along the edges of the block that would stabilize while sanding and also be progressively sanded away.

I spend too much time at instructables.com