Here's one I made. I based it upon an image I saw of a double cavalry holster. It's basically a leather bucket which does cover and protect the hammer/frizzen, and can be carried on either side (the space required for the trigger guard is roughly equivalent to the space for the lock mechanism).
The back has a 2-way loop, allowing it to hang on either a belt or a vertical strap (I often put it on the strap of my shooting bag).
The back has a 2-way loop, allowing it to hang on either a belt or a vertical strap (I often put it on the strap of my shooting bag).