This is a one piece casting with separate arm, which means I think it is likely to be FN 44 Lancer of the Guard. The horse has been remounted on a different figure's base. In stripping down and refurbishing I found the head is plastic, probably an Airfix one from the ACW artillery or Wagon Train sets. I have regluedthe horse to its base and now need to identify a donor arm for the figure. My normal procedure is to spray figures with plastidip, a rubberised coating which dries matt and prevents any flaking of paint from plastic figures. This has the added benefit of strengthening the joins of any converted parts.