Mike, try Muir direct. www.muir.com.au/contact
. They recently supplied another TFer with parts, or more, I think from within USA. One way or another you should get help, they are a responsive company, but remember it is Saturday here.
Never seen one with twin gypsies before, but it should be a good buy if condition is good. Usually if it is an alloy case you get some corrosion under the paint, cosmetic really, latest ones have a composite cover.