If you mean a "factory" conversion,( 1851/1860 RM conversion, man with no name 51', open top) and not a conversion cylinder (Kirst/R&D) to put in a percussion revolver, then yes.
a factory conversion, i'm parshal to the 1860 colt, and no one round here sells em. i noticed buffalo arms has them,guess i'll call them and see what they say.