During WWII and onward, normally large US Navy warships had a contingent of US Marines aboard, as part of the vessel's crew (Marines assigned to the warship). If any LARGE US Navy warships were in England, US Marines were probably present too.
Age restricitions vary by branch; however each will enlist an individual at the age of 17 years old with consent of both legal parents: US Army 17 - 42 years old US Navy 17 - 34 years old US Air Force 17 - 27 years old US Marines 17 - 28 years old
It's possible to obtain the names of the 14,838 US Marines who perished in Vietnam; but it may prove to be a daunting task to obtain the names of the remaining 375,000 US Marines that fought in the Vietnam War.
6821 Americans died, but none of them were soldiers. Soldiers belong to the Army, and it was the US Marines who took Iwo Jima. So all the casualties were Marines, or medics serving with the Marines, who are US Navy Corpsmen. There were also 19,217 US wounded.