That looks like a standard CWU-27/P flight suit, although I've never seen one in that color. The real thing only comes in a handful of colors and is made from flame-resistant Nomex, but several vendors sell variations of this suit in various colors and fabrics -- just make sure the zipper and pocket arrangements are the same, as these can vary a bit, too. Perhaps you could find a used navy or royal blue flight suit and bleach it down? I don't know much about how these suits respond to bleaching.
If money is no object, try Gibson and Barnes. They offer a "Sentinel" uniform in a variety of colors made of a cotton/poly blend (more comfortable than Nomex), and can even make custom uniforms in any fabric you like.