Not a replica but i have 2 ruger old army pistols I intend to use for close range shots during BP season. I think most of the replicas won't hold enough powder to make a clean kill on deer, unless u have a Walker replica.
I only have Navy 36cal pistols so no deer hunting with them. I think a Ruger old army or a Colt Dragoon or Walker could get the job done at close range. 20 to 30 yards would be tops though.