“Eligibility Checker” plugin? | WordPress.org

Hello everyone, I was asked to add an “Eligibility Checker” to a page I am working. It will have certain postal codes (zip codes), limited ones, so if the person adds theirs, and it is on the list, it should say, yes, you can apply, if not, it should say, sorry. Not applicable. The program will NOT take them anywhere. Just that. Any ideas of what I can use? Thank you

The page I need help with: [log in to see the link]