We can get 130 units in Australia from SparkFun. If you order today, we can dispatch this stock between Oct 28, 2020 - Oct 30, 2020.
This is a small device called a reed switch. When the device is exposed to a magnetic field, the two ferrous materials inside the switch pull together and the switch closes. When the magnetic field is removed, the reeds separate and the switch opens. This makes for a great non-contact switch. This switch can carry up to 1.2A.