Greetings Alan, just looked in the American Social Security Deaths list and found the following:
MOORHOUSE, LESLIE Soc Sec No.564-74-6061 Registered: CA (California) Born:3 Oct 1900 Died: Dec 1984Europe Last known addresses: United Kingdom (London),Ref. XX800 58350 (Maddock, North Dakota) 4g.
Perhaps this is your man as he does have English connections.The only other Leslie Moorhouse registered Lived in Michigan (b. 1903 and seems all American)
There are records of two Leslie Moorhouses in New Zealand born 1904 and 1908. The latter one has parentage from Manchester (Frederick Curtis Moorhouse son of David Adman Moorhouse (horse dealer, etc)) They emigrated here (N.Z.)in the 1880's. As Leslie is a very uncommon first name for Moorhouses I thought you might make a connection, though this is obviously not the sea captain you are actually seeking.