it is very difficult to chose from the tremendous number of movies, but maybe
Aston Martin DB5 from Goldfinger - http://www.imcdb.org/vehicle_1820-Aston-Martin-DB5-1964.html

or Volvo P1800 from The Saint - http://www.imcdb.org/vehicle_107144-Volvo-P1800-1962.html

or Isotta-Fraschini Tipo 8A from Sunset Blvd. - http://www.imcdb.org/vehicle_54604-Isotta-Fraschini-Tipo-8A-1929.html