In 1960s, only 19 original Aston Martin DB4 Zagatos were built. They were instant classics.
In 1991, Aston Martin and Zagato built four "Sanction II" DB4 Zagatos
recreations using four left over DB4 chassises from the 60s.
They were built to exact specification to the original DB4s and were sold over $1,000,000 each.
In 2000, two more DB4 Zagato recreations were created by a different company based on two left over DB4 body shells from Zagato. These two "replicas" were called "Sanction III" DB4 Zagatos.
They were not official products from Aston Martin or Zagato, but offered an almost exacting glimpse on
a car that might have been created if production ever increased beyond the original 19 cars.
(en.wikipedia.org & supercars.net)
(Photos from caradisiac.com)