You're in NSW, its different for Victorians (as it stands) - look at the very 1st post to see the difference (i.e $$$).
And as my last post and pic alluded to, I can readily go and buy a "prohibited weapon" from any number of shops for just a couple of dollars. There is ZERO difference between the two in the eyes of the law, but I can go buy as many as I want right now.
Common sense is severely lacking in this thread.