thanks so much for your clue to the origin of this item! Now I can narrow it down to a French or Italian manufacturer.
How it ended up at a flea market in Sydney, I have no idea!
It is in perfect condition- no chips or cracks, in fact it looks like it has never been used for whatever it's purpose happens to be.
The stall-holder I bought it from had no idea what it was, & even though it is not really the kind of item I'd normally buy, the mystery about it attracted me.