Paul McCartney Engaged-Again
"Nancy and Paul are getting married - ring and all. Very exciting," the source said.
The couple, who appeared together Monday at the 2011 MET Costume Gala in New York, began dating in the Hamptons during the summer of 2007.
This will be McCartney's third marriage. His last marriage, to former model Heather Mills, ended in a nasty divorce in 2008.
According to PEOPLE, McCartney is 17 years Shevell's senior.