Utilities & Mobile Utility Power Restore Alert Device

Any suggestions on where I could find such a device in Dumaguete? (I'm guessing Polaris or Uymatiao but I'd like to know if I'm wasting my time going in town/traffic for this....or if the locals have a certain name for these devices so I can ask if they have it without getting the deer in the headlights look.)

I'm looking for something like this:


If such a thing can't be found here are their any suggestions on another (and safe) way I could know when the utility power comes back on?

My setup is rather simple: I have a small crappy Chinese no-brand-name-no-frills generator (pull the cord and it starts, flip the switch and power comes out). Utility and generator power run into a DPDT (double pole double throw) switch which goes straight into the fuse panel. When power goes out I start the generator and throw the switch.