Turbull has done real Winchester 1885s. My guess is if you send him a Miruko he could handle a custom build. here is an 85 from his website.
http://www.turnbullmfg.com/gun/winchester-1885-high-wall-log-5159-turnbull-mfg/If you want a rimless round, i believe you will be limited to a Miruko 85. The Italinan and American made guns (such as c sharps 1885) are origional design guns that require a rim.
