Maybe you could email an ebay seller selling each of those bags with tags still and ask them to tell you what the sku number is? I'm assuming you're trying to use it for an item locater? I -think- the upc should be the same even if they got it from a different store, because I think all the department stores use the same sku number system...
You could also try nordstrom's online help. They got me the UPC for a bag that I was looking for and told me which stores carried it although I ended up buying it elsewhere.