Big River soundtrack with Aussie cast

I am so desperate for the soundtrack of the BIG RIVER musical with the Aussie cast. If anyone can tell me where I can obtain a copy I would be so so grateful. We have almost worn out a copy on an old tape & would love a CD to have. Our children have sung it in the car for years & even though they never saw it (I did, though), it has been their favourite tape of all time!!! Please can someone help me....Thanks so much. My email address is free4us@tpg.com.au Please put BIG RIVER CD on the subject line & it wont get deleted.......thanks again.