Outer Limits 4x4 Board

Giday, I have a NA 2.6 pajero that is starting to whine in a few gears. Does anyone know where I can either pick up a reasonable priced imported or second hand gearbox. I have read that you can still pick up brand new ones still for around $1500 or so; is this true? and where can I get them. I live in Brisbane.

Hope someone can help