a jacket and full skirt ensemble worn in several key scenes in the 1939 movie has fetched $ 137,000 at auction .
the has faded over time from its original slate blue-gray color to become light gray .
private collection james tumblin learned that the dress was about to be thrown out in the 1960s and negotiated a deal to buy it for $ 20 .
other top selling items from the auction were a straw hat worn by leigh that sold for $ 52,500 .