miss MM back door cylinder.

hi, i use to leave in LA and i have an old friend who give me the lock cylinder from his step father who own the safe lock smith from 50's up to 80's.the cylinder from back door of miss MM when my friend step dad got called in 03-15-62 to Beverly hills house he say he met miss MM and ask him to change the old cylinder and he ask the old one if he can have it and she give it to him and he put a name tag in each side the date 03-15-62 and Marilyn Monroe name in other side. this cylinder with a letter and the receipt is missing.pls, help me if this have a Record from Miss Monroe or maybe someone can help me.thank you so much.