The hose nozzle mentioned by Don recently on A Current Affair is a Ladco Blaster Nozzle. RRP is $6.94
It is available at some Bunnings stores and some Mitre 10 Stores. If there are none available Bunnings should be able to do a special order for people since it’s on their Special Order List. The product information is Ladco Blaster Nozzle Part Number CB707.
There is also a brass nozzle available at Mitre 10 called a Jet Nozzle. It is made by Neta and the rrp is $7.90