I thought you might be struggling with the physical side, I'd noticed another of the posts where you mentioned it. To top it off about the caravan park rules, sucks.
Here's the contact details for ZF in Sydney, easier for us to find stuff than your internet. They will need the serial number of the box (identifies the exact version) to give you an idea of replacement.
You will want to get a new rear input seal for the transfer box at the same time ideally. Give them a call first thing on Monday to get a price and timing - you've seriously nothing to lose in comparison to straight second hand job. The rules of forum state we are not allowed to bad mouth companies, therefore I can't state one way or another about what the second hand options are like. However, most second parts places will do no more than take a box out, pressure wash and send up. There will be no idea most likely of the actual condition other than the odometer reading of the donor vehicle, I would be suspicious of statements to the contrary unless you get a box from a movable vehicle or the owner of the car.
However, if ZF is too expensive then I guess 2nd hand is the only option.
You are 36h drive for me otherwise I'd head up to lend a hand - feeling for you mate! Is it insured for a mysterious and unfortunate fire?
ZF Services Australia Pty Ltd.YOUR TOLL FREE NUMBERS IN AUSTRALIA
14 Lidco Street
Arndell Park, NSW 21482 Pavers Circle
Malaga WA 6090ZF Service Desk
24/7 Technical Support
1300 ZF TECH
(1300 93 8324)ZF Sales
1800 ZF SALES
(1800 93 72537)Email:
customersolutions.au@zf.com
Phone: +61 2 9679-5555
Fax: +61 2 9679-5500Email:
customersolutions.au@zf.com
Phone: +61 8 9248 1096
Fax: +61 8 9248 1093