David has written a post about Safari Outfitters Ltd. who produce left hand custom big bore rifles.
Safari Outfitters Ltd. Is a high-end gun store in Salt Point, NY, that is owned by Niles Wheeler. Niles is one of the finest human beings in the world, shoots left-handed, and has a soft spot for the directionally challenged. There are almost always a couple of nifty left-handed rifles (and sometimes even shotguns) in the racks, and since he knows a lot of sinistral shooters, he can often get hold of something left-handed when others can’t.
Below is a photo of the custom .416 Taylor rifle he is referring to in his post.
Read more here.