Vodafone Australia’s Xperia M is the C190x model - the single SIM version of the handset, which at the moment runs Android 4.1.2. The dual SIM model, C200x, is already running Android 4.2, and we’re assuming that it, too, will get 4.3 at some point.
Vodafone also seems to confirm that 4.3 Jelly Bean updates for the Sony Xperia SP and TX are coming soon - just as we reported not long ago.
The Xperia M is currently widely available around the world. You can even buy it in the US, via the official Sony Store, where it costs $229.99 (unlocked, available in four color versions: black, white, purple and yellow).
source: Vodafone Australia via Xperia Blog