There was a man named Arthur John Rambo who did die in Vietnam. He was a married twenty-four year old soldier who was killed in combat on November 26, 1969 in Tay Ninh Province. His name is listed on the Wall, 16W, 126.
There was also a Special Forces Sgt Rambo. He's a retired CSM now. Can you imagine all the crap he had to listen to about his name?