This is a guitar of Robbie Robertson's personal collection as seen on his official website. He has played it now and then.
"I have a 1901 Martin OO-42, a 1919 Martin OO-45K that’s the only one in existence – it’s the guitar Emmylou Harris played in The Last Waltz, a beautiful koa Martin, and I have the only one in the world. So they started making that guitar – all in koa or with a spruce top." - Vintage Guitar interview