One owner 1964 Shelby AC Cobra 289 sells for 475,000

CSX 2305 is one of the few one owner Cobras that existed.  found on http://jalopnik.com/5852452/one-owner-shelby-cobra-sells-for-475000

This original Shelby Cobra was purchased by Ed Johnson at Kansas City Ford in 1964. Johnson was the county Medical Examiner, and he raced and autocrossed the Cobra on a regular basis, earning numerous trophies and awards along the way. These awards, along with extensive documentation, will accompany the car to its new home.

I know of three others.

You ought to know I've already posted about them, and taken photos several times of the Hank's CSX 2227 http://justacarguy.blogspot.com/2008/07/hassler-spring-was-to-counter-top-heavy.html , and a gallery of Carroll's CSX 2001 http://justacarguy.blogspot.com/2010/12/carroll-shelby-prototype-cobra-1.html .

The most famous person and longest owner of a Cobra besides Carroll is Herbie Hancock CSX 2006  http://justacarguy.blogspot.com/2008/03/herbie-hancock.html  or read the story about Herbie and his Cobra at http://www.clubcobra.com/forums/all-cobra-talk/96650-hank-williams-cobra-289-did-he-order-two-barrel-originally-2.html