Hi J.,
Would love to help out. I have been there! OK, first I would try with the Bakeries in the area or even in your local Grocery Store. For instance just today I went to Fry's Bakery Dept. and purchased a "Spiderman Kit" for a cake (you know the cakes that people order-it's part of what they use to decorate)for my son's 5th Birthday Party Cake. I had been looking all over for a Spiderman that was not going to cost me $10 so I was happy that it was only $6.00! It's part of what they use to decorate).
So, I know for a fact that if you go to any Bakery or Grocery Store you should find it. I also would not go by just calling. Because especially a place like Wal-Mart or Target you can not always trust or rely that the person looks very good or in some cases forgets to look while your on hold. Just go down there if you can. I would not be surprised at all if they have it too. I was just at Wal-Mart last night (again, getting Spiderman favors for my Son's BD) and I think I saw a section on "Thomas".
I'm confident and sure you will find one. Don't give up.
Have a Great Party!
A.