EmilieJax

Hey all - 
I have a client who wants to add a plugin to their site that will allow the ability to plug in a zip code and have the user alerted as to whether or not they currently service that area. 
I thought zipfinder was the answer, but that's just for specific locations (not a map delivery zone type plugin). 
Has anyone had experience with this? Any good solutions out there?
Thanks in advance,
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