Hard Enamel Lapel Pin Making

I’m thinking about making a few custom lapel pins and am seeking advice.

My thought so far was to cut a small square of brass, etch the design, clean the edges, fill with enamel, and then solder a pin to the back.

I’m open to alternative ideas. If etching is the best process, is this something that would be acceptable to do at DMS and if so, where?

Below are a few examples of the types of pins I’m thinking of.

We have ferric acid available in jewelry.