Sorry to bump, but trying to avoid someone making the same mistake I did.
The adapter that Loren linked is NOT suitable for Rachio. Rachio requires an AC-AC adapter. The AC-DC adapter Loren linked will cause issues with your Solenoids (I learnt the hard way).
Refer to this thread:
In Australia, searching Google for “AC2410” should get you what you want. Here are some I found (yet to receive one to verify):