The dream of “being discovered” is on parade at a casting call in Novosibirsk, one of several Siberian cities that supply the pre-adolescent, doe-eyed, “Russian look” models most desired by the Japanese fashion market. Ashley Arbaughscours rural beauty pageantsfor girls, typically poor, mostly looking for a way out, and sends them off to Tokyo. That journey, marked by deceit and exploitation, is the subject of “Girl Model”, a documentary feature by David Redmon and Ashley Sabin. Together, David and Ashley have produced, directed and edited seven documentary feature films. Their latest,“Girl Model,” makes its broadcast premiereon PBS’s acclaimed POV series on Sunday.