Flying High could do it much cheaper, it's such a light item, they could just send it in an envelope
Does the Royal Mail have a solution like Australia Post, this is actually quite economical to do it this way, I've bought heaps of things that don't ship to Australia or are too expensive to ship via the retailer.
ShopMate
Under this Shopmate method the Flyinghigh plate will cost me 80 aud delivered while directly from them it's 230 aud.
It's still too expensive as you say for a piece of plastic and you still need the
P4P mount to put on it.
So the DJI official mount for the Mavic and Spark controllers is the cheapest and most efficient mount for the
CS