You could probably make your own. I just Google "how to make an ant farm" and it sounds pretty easy. There are tons of ants out in the yard. I'm sure you can get them on a park if you don't have a backyard. Good luck!
Online would give you multiple options & prices. PetSmart would know of local shops that would have them if that's what you're wanting. Give them a call.
Call Wild Bird Habitate I think I saw them there. If not, would call Pet Smart etc before going anywhere. Imho
Online is easiest
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