When I was working at a big electronics manufacturer that had many CNC
machines, in off times people would make chess set pieces. Aluminum
for one side, brass for the other. Something that can be made, sold on the
net and shipped easily.
Steve

Hmm, how about making Metal pinball posts?
T nuts, shooter housings parts with custom logos?
They are expensive and a lot of times there are hard to find specific sizes.
Pinball league ID tags?
Tournament prizes?
Glass rails and guides?

Seems like the chess set idea is a good one too...

I would image The amounts you’d sell would not make it worth while but only you could answers that question.

A sister company I work for has patents on ship flanges and clients include Lockheed Martin and
GE. I can’t help with specific leads but my advice would be to network with companies that make parts for companies that have huge government contracts.

Custom aprons.