I'd be willing to do the escrow (for the bitcoins) as well as to conduct the raffle, which will be provably fair. No need to send me the miner, you can send it directly to the winner, and I release the coins after that.
Thanks Dabs for the offer, I'll keep it in mind.
I appreciate all the feedback I have received on this topic. My goal was not to scam or rip anybody off, I was just looking for a novel way to provide miners with an opportunity to get a single on the cheap. I might do something like this in the future, and donate 80% proceeds to charity.
Due to the lack of interest and positive feedback, I have decided to sell my third Single on ebay:
http://r.ebay.com/TOa7nU