Went to my TrU (I've moved, so northern Virginia now) for some Toys 4 Tots shopping, and they had a pretty full box of the yellow bag wave. I reached in and grabbed three and wound up with Skywishes, Lyra, and Fluttershy. :/ Not my best blind grab, LOL.
They also still had a pretty full box of the Wave 4 series, as well as some Wave 3. I think I am going to like my new TrU.