Sorry I didn't post sooner, but I had a really busy end of week. No luck on the button which frankly amazes me. First that the manufacturer whoever it is, didn't mark their equipment and second that I cant find any reference to the button on the web. When I couldn't find any mfg info on the buttons I prepared my customer to the possibility that I might have to change buttons and plates, not much else I can do. I plan to change out all the hall buttons and save the button modules for spares in the COP.
Thanks to all for their ideas and suggestions