The website shows they currently do. Go to the website, select a store and search "dog door". It shows in each item how many the location has in stock.
Make sure the installed doggy did its the right size for your pet. I suspect Lowes could also custom install the right door for you. There are a lot of kinds of pet foods with different lockout features and in different sizes. Make sure the door you get doesn't cause more problems than it solves!
It is always good to check website prior it to trip. This is especially important for larger ticket items.
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