Hi there,I'm in a wedding in August 2013 and am looking for a gently used dress. I need a David's Bridal F14169 in Malibu. It's called Strapless chiffon with layered skirt. I would need either a 10,12 or 14? I haven't tried one on yet and don't know how it will fit, but assume I can have it altered? Any help is greatly appreciated!!