"Embossed?" You are thinking of leather carving. Great for patterns. The best carvers can do images, but I don't think it generally looks so great.
If you want photographic results, like for faces, there are other ways.
I have seen guys have Harley seats done.
Google leather tattoo. There are several ways this is done.
It need not be a case maker. A case maker can supply the leather, it can be sent to an artist. Pick your case maker, and pick your artist. And a case maker may know an artist. Ask John Barton.
Castillo makes cases, and they to leather "tattoo" wraps which are actually burned on images.
http://castilloleathergoods.com/?cat=7 Maybe they'll tattoo a case?
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