Here you go .
The tool your audio project requires.
Add some sound with our Piezo buzzer siren! This buzzer may be used whenever an attention-getting audible warning is needed. The siren is perfect for security systems, over and under-limit indicators and power failure alerts. Operates on 6-14 VDC, with 150mA Current at 12V. Buzzer Tone rated at 2,000-4,500Hz.
Got to radioshack.com and search for "piezo speaker" there are half a dozen of them. I am using Catalog #: 273-070. I mounted it with velcro under the left side cover where the HD alarm module is clipped in.
Anybody have the Radio Shack part number? Or the number/make of those piezo buzzers?