Hello, Cecil,
This meter is no longer being made and can't be obtained from O/S ( I tried some years ago when mine began giving trouble).
I changed to a Skywatch Meteos Anemo shown here:
www.instrumentchoice.com.au/collections/handheld-anemometers. You will see that there are 3 models available in this configuration and they offer slightly different info and features. The setup for average windspeed is a bit slow. Output in knots is easy
The meter is bulkier than the Windtronic but essentially gives the same info, plus, it also shows the wind chill (which may not be required in WA, so perhaps the Eole model is better there).
Overall, I found it to be a good replacement for the Windtronic.
Hope this helps.