The clue is "wixsite," which is a very low end website service. Sorry for that to happen. Fortunately there are a large number of other suppliers.
This is their facebook account
https://www.facebook.com/Custom-Avia...3130251166558/
The address appears to be in a residential neighborhood.
https://vymaps.com/AU/Custom-Aviatio...3130261166557/ if vymaps is correct, though this isn't near Canberra which vymaps places it.
The last updates were in early 2021; the innocent explanation is there is an order system still running but the owner has died. On the other hand straight-up scamming is also on the table, playing on the Veterans angle for sympathy.
Perhaps contact
https://www.camaust.com.au/ which looks like a reputable dealer - someone there will very likely know what's going on and point you to getting the model you want.