Pattern search, Roksanda Ilincic dress from 2011 (or so Sewing Machines Parts and Sales in Los Angeles

Does anyone know what pattern would work best for this dress? Florence Welch (from Florence and the Machine) wore it in 2011 and I still love it. This is the back, although personally I would keep it all one colour. The main parts i love about it are the interesting lines across the abdomen and the flowyness; I am afraid of what appears to be ruching (have never done)
Thank you for your help!