I've responded to the dispute saying that it was definitely sent and because they opted for not sending with tracking, there is no tracking number. I have stated that I have the receipt and will send to them if they give me an email to send it to since I don't know how to attach via the message from the dispute reply. I have yet to here back from the buyer and this was since Friday. Unfortunately the Australia Post receipt just says Russia but not the full address. I guess I'm not going to here back from her and she's just going to wait to close off the case and try for a refund without any contact with me.