Hmm.. I don't think he's a bay though, because he does have a faint dorsal stripe, and he has lighter on his muzzle, and more orange than most bays.
My friend has a dunalino that looks like a palomino, but she has a faint dorsal stripe, she is registered dunalino.
I'm not really sure what his color is, but it isn't a bay.
By the way, I know what a dun is, I have a red dun ;)
He knows when you're happy He knows when you're comfortable He knows when you're confident And he always knows when you have carrots.