So, super UPDATE...I've received my cheque, and looks like Australia Post finally took responsibility all thanks to an escalations consultant by the name of Paul Le Good.
Case Closed.
Glad you were able to get, if not a positive outcome, at least a satisfactory one.
Thanks guys. Yeah, it turned out OK...i mean, it still doesn't defeat the fact that my artwork is damaged, but yes, they did refund me the full amount I bought it for.
Have flicked an email to Freddie to get more artwork to make up for it.