I ran out Piezos and was wondering around looking for cheap musical greeting cards in DOLLAR TREE when lo and behold hanging on a pegboard was the answer for my quest, were these little blessings called widow alarms! Grabbed a half dozen and stripped them out. Not only did I wind up with Piezo pickups they yielded 6 magnets to use as small parts holder's (maybe humbucker parts, don't know yet), 24 L44 batteries. The back of the cases might make pick up covers.
Knowing that all piezos aren’t created equal, my question is how do they sound in a guitar?
Can't answer that until sometime next week when I get home. Can't be any worse than the bunch on eBay from China, about a 10% failure rate. My neighbor and I split a batch of 20, just once!