There should be plenty of inventory left in stock in various companies warehouses. You can always try the other color part #'s too. It's not your fault someone sent you the wrong part #, so they should pick up the return shipping. If you find more stock from various vendors, have them shoot you a quick picture of the sprocket before they send it out in the mail. If they want the sale, they should do this no problem. Fidanza makes those in batches based on volume of inventory movement. It is possible that they're is so slow moving, they're not going to re-make.
I personally have dealt with Fidanza when I had 50) 16V Masi cam sprockets made. They were good to work with. Treated me like I was a valued customer.