Need help. I Bought a non excisting horn relay on Ebay

I bought a NOS horn relay on Ebay. It was one of those with the Buy it now option. The seller had some 4 or 5 of them left when I put it on my watch list. Yesterday only one was left and I hit the Buy it now button and paid for the horn relay via Paypal. Today I recieved a mail from the seller:
"Hi, sorry my friend, but we are out of these relays. Please accept our applogy on this, we will send out your refund now.
Xxxx Xxxx"

One minute later I got my money back.

My answer to him was:
"Hi Xxxx
When I purchased the horn relay you stated that there was one left (mine). How come that all of a sudden there is none left?
Anyway, thanks for the quick refund of my money.
I still have to decide how I am going to rate this."

An his answer back to me was:
"Please don't leave me a negative, it was my listing services fault, not ours. Can't I make it up to you?
Xxxx"

Well, my problem is that I bought a thing (the last) and I can´t have it beacuse it never excisted. He claims it is not his fault but his listing services.

The seller has over 99 % positive feedback.

I am still debating on which feedback I am going to give him.

What would you do?

there are around 6.8 billion people living on the world as of July 2009. That number will increase by about 212,035 every day.

Read more: http://wiki.answers.com/Q/How_many_people_live_on_Earth#ixzz1Fe4rWtBP

Do you think maybe one of those other guys might have been hitting buy it now a fraction of a second before you did?:wack: