Is there any way to date it to a specific year? From what I understand it was made Early War, but are there any indictors to pin it to a specific year like 1940? If not then by Early War I assume the years of manufacture would be 1939-1941, correct? Also I have one more question. In regards to "maintenance" of the sword I've seen people say you should oil the blade and not let it dry out, is there a certain type of oil that is recommended or would standard Hoppes/Ballistol work? Thank you.