... If my memory serves, the "Lanchester" was simply a copy of the early German SMG (MP ??? ) with a bronze magazine housing and bayonet "boss" to take the British 1907 ... maybe a view, copy or even an original ,could be found via the German version ?? ...... Only handled one once, and that was way back, just after the last Ice Age, and I think it had a rear sight similar, if not the same, as the SMLE No.3 ? Another source of info. could be Ian Skennerton / or one of his books, dealing with Commonwealth Military Weapons. .... Good luck with your search ! .... David K.