I know exactly what you are talking about; I have seen them used a lot with cash registers and sometimes with computers. I think your best bet would be from one of those computer hardware catalogs we all get in the mail.
PI Manufacturing in Walnut, CA that has that kind of stuff. Their number is 909-598-3718. It is on page 27 of their spring catalog.
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Ed
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How come there's always enough time to go back and fix it a second time?
