Zombie Limbo

Just a quick update on things. Regarding the Zombie Sensor; I have a lot of the parts to make more units, except for the speaker. The piezo speaker had been on backorder from Mouser for several months now. I've been trying to find a replacement, with no luck. The original part can be found HERE.

All of the replacement candidates tested are not as loud as the original part. The design of the original part is a bit different - and the video below shows what I'm up against. 

If anyone has ideas on ways to solve this, please email me at "rwb134" using Google's fine e-mail service. I really want to get more of these made, especially so I can have them ready in time for TagFest 2015 this year.  Keep your fingers crossed.