CephaloPOTUS

Technically not by convection because that is the movement of fluid to transfer heat in and out of something, like air conditioning. The bath is not a moving fluid it is a simple constant temperature. The spinning moves the fluid inside the can so more of it touches the aluminum wall, which is being cooled by conduction with the ice bath.

There are dozens of choices that work great for twenty some dollars online here in the US and don’t even replace the seat.

You can definitely get one in Australia. They are like $30 on the internet delivered right to your house and attach to your toilet in under 5 min.

All normal modern ones are just a simple toilet add on. Take up no space whatsoever.