This is not good selling practice and the seller should check prices before they list items.
Really, the seller should refund you immediately if they are not going to complete the transaction.
Message them today and state that, as they are not going to complete the order, you expect an immediate refund and you will look for the email from Ebay saying the refund is being processed to arrive very soon.
If they don't refund immediately, you may have to wait for the estimated delivery date to pass.
Check the email you got from Ebay when you paid.
One day after the latest estimated delivery date, you must open a case stating you have not received your item.
"There are two ways to be fooled. One is to believe what isn't true; the other is to refuse to believe what is true.”
Søren Kierkegaard, Danish philosopher (1813 - 1855)