You might find something period that was designed for a WEBLEY .455 but just about anything western or period would have to be an antique itself or be home made or custom made. Walter Austin in the Victoria B.C. area may be able to make one. The hard part of something that is not a mainstream gun , is how do you make a holster if you don't have it in your possession. Common guns are made from metal or plastic forms of the gun , odd ball ones maybe can be made from something close then wet the holster and stretch it to fit the odd ball. Good luck.