Need a small, light, low power beacon transmitter

Hello, i need a very small, light, low power (working at 1.5v battery) beacon for an transmitter that i can receve with a common AM/FM/LW portable radio. I intend to use it to locate my dog (is a small chiwawa). I live near a forrest and my dog is keep dissapearing in the woods :)). I've tryed this sites but i cannot find some of the components (like a xtal FM type) and on the other site is seems to easy to be true (and i cannot understand on what frequency works).

Thanks ...