My 2011 Suncruiser has a HWH system which is probably the same as yours. The buzzer is not part of the panel and is mounted on the firewall. I did not remove mine from its mounting bracket, but this type device usually has common "Faston" connectors. Customer Support at HWH is great and can help you get a replacement. When you do install the new one, mind the polarity of the connections. The buzzers have a "+" and a "-" side.
Mine was working as designed, but I found the buzzer really annoying. I added some simple circuitry that would allow me to disable it when it wasn't needed.