42RH / A-500 in a Duster with pictures.

Hi guys.

Im currently into a long build of my Aussie Valiant version of the 69 Dart and I am thinking of going with a 42RH.
As this trans is not very common here is Oz at all, could someone give me an idea of where I could locate one in the US to then sea freight it over to Oz?

Thanks for any help
Paul