are you sure you got scammed? Do you know if he cashed your money order or if thats the one he supposedly sent back? If not he should have the bottom part of the money order with the numbers on it that he can give to you. I bring this up cause a similare situation happened to a friend of mine on e-bay were a guy sent the money order along with the bottom part to a seller so there was no way of knowing if they cashed it. good luck.