I still haven't found anything referring to a mark of "L.E.M.", and no makers with any combination of names that fit the acronym, in any stretch. I've been looking in my reference books, going back to the early 90s, like Bruun, Andrew Rose's "The Collector's All-Colour Guide to Collecting Toy Soldiers", and Norman's own "Toy Soldiers". Nothing in O'Brien, either. Web searches have also failed to return anything that can ID these. (A lot of disambiguation needed for the character of "Lem" in the movie, "Toy Soldiers", though.)
You'd think that with such a clear mark, someone would recognize it.
Also, in terms of the style of their sculpting and painting, they do remind me of Edmunds, as was mentioned before, but they also remind me somewhat of Blenheim or Marlborough. Not saying that they were produced by any of those three makers, just that they look similar.
Still looking...