You should take a look at James Avery jewelry. They have a selection of dog charms: http://www.jamesavery.com/catalog/search.cmd?form_state=searchForm&keyword=dog+charms
They offer engraving--and their hand-engraving is gorgeous. They also sell an engraveable heart charm and bracelet that's a little similar to the Return to Tiffany's heart charm. http://www.jamesavery.com/product/Smooth-Engravable-Heart-Charm/156127.uts?keyword=heart+charm
I think their sterling is every bit as good as Tiffany's, plus their price and selection is better.
Thanks! They do have adorable charms! And as you said their price is much much much better

I have a love/hate relationship with T&CO, I'm fully aware that you're paying for the name, but at times its pretty absurd.