Try getting onto Chris Pierce of Spirit design. He lives here in Victoria and does a lot of Victorian Stuff.
Or if not he can point you in the right direction.
Rob Carpenter makes a lot of Victorian freight cars however I do not have his contact details.
Brunell Hobbies might be worth a try along with Trainworld in Brighton Victoria, and Casulla Hobbies in Sydney.
There is a lot more around than ever before.
Good luck.
Rod.