On this page is a selection of holsters which I have made. I plan to do more of this work in the future and will on day make a full cowboy rig!
Colt Single Action Army Artillery, oiled russet mexican loop holster
Remington 1858 Antiqued with wild rose tooling
Holster Making in the UK
If you are in the UK and you would like to make holsters you can look into buying deactivated guns, blank firing guns (e.g. by Pietta) or airguns none of which require a license. Always follow safe firearms handling procedures.
Here are a few books which I have that you might find useful if you would like to make your own holsters and gun belts: