The 1980 SR 500 in my avatar isn't really rare. Not a lot sold, however.
I did own a 2001 Ducati 600 Monster Metallic. Not many 600's came in and only one of 50 600 Metallics that came into the U.S. It looked pink in the bright sun. I later worked with a Ducati North America employee who told me that the paint scheme was a marketing ploy to attract women riders!