I've made two dice bag patterns in the shape of the dice.
The first one I made is D12 (e.g. pentagonal dodecahedron):
https://www.etsy.com/listing/851782451/leather-dice-pouch-pattern
And then I though of making one that doesn't need stitching and made a standard D6 dice with rivets as pips:
https://www.etsy.com/listing/1106903797/riveted-d6-leather-dice-bag-pattern
I am working on D20 as well, but wonder if these are interesting to you all?
Should make the whole set of different dice dice bags?