Thanks guys, I've calmed down somewhat now.
I was only doing about 25 and was stopped by the time the little rat hit me. I couldn't believe that he wasn't even going to try and stop. I think it shook up the driver coming the other way more than me
It could have been worse. My Dad used to work with a really decent guy that flattened a kid in similar circumstances, nothing he could do to avoid it. He didn't drive a car again for something like 15 years.
I did pick up a full size alloy spare some years ago, so barring any further catastrophe that can go on when it's time to change and the space saver can come down off the garage wall.
But I had plans for that wheel as a coffe table