A U.S. or Canadian Postal Money Order in a failed transaction would constitute mail fraud. I'd bring the Post Master General onboard for the discussion. That would eclipse jurisdiction boundaries and they love to chase these things relentlessly.Years ago when I was leary of this type of thing and before PayPal was around, this is what the bank suggested to me. They said it was the best thing to have if things went other than as anticipated. Just notion for you to follow up.