I would suggest that you first decide which ears you likely want and then go into any store. If they aren’t available in that store, ask where to find them. There are a number of styles that will be available in most stores, but some either sell down or end up only having stock for a variety of reasons in certain locations.
When you enter MK, the ENTIRE alert side of Main Street is like one very long store - all of the shops are inter-connected and you can pass from to the next, all the way to the end, without ever returning to Main Street. You could go through there either upon entering or on the way out as a way to get past the crowds on Main Street as well as a way to “shop” for ears.