If he says no, then just remember that on a future purchase.
It sounds like a communication error. I have ordered wrong parts from Coz before because we obviously got mixed up. It's not worth the shipping to send it back. So in the future when i order, i make sure we're both on the same page. I have a part in question now, but i won't know until i start piecing together my engine. I've learned part numbers are key. My mistakes have always occurred when i can't find a part number and it's not listed on his site.