Howdy, 67. Welcome to the forum. We're looking forward to seeing your posts.
You have a good eye. That holster is a Cheyenne style and I copied a Meanea holster for the pattern. That was before I found out that Will has a good pattern for it available, like Outrider said. I think he also has a tooling pattern included if you want to make a full tooled one. Give him a call or check his website for that pattern.
Outrider, you just beat me to telling him exactly that. Good thing, too, since I've been tied up all day and he probably has the information already thanks to your post.