By all means, start with the film archives of the Library of Congress.
Also, you might contact the American Film Institute in either Wash. D.C,
or in Los Angeles.  L.C. First St. and Independence Ave. SE ,D.C.20003.
Telephone: 202 707-5522.  AFI (in D.C.), AFI Theater, Kennedy Center,
Wash. D.C. 20007. Phone: 202 828-4070.   Good luck!