[Arran]

I think it's actually called Paldao, I'm not sure if Australian Walnut is the same as orientalwood which is what Paldao is, I have some Australian walnut veneer and it looks more like ribbon mahogany (stripes) other then the greyish brown colour.. I don't believe it's that expensive either, Paldao is a huge, fast growing, tropical tree in New Guinea and the Philippines, so don't think the wood is particularly rare nor expensive. Have a look on fleabay for some.
Regards
Arran