Well if is "i checked the current conversion on google" ...

came, out to be $12.0564808 Australian dollars...
so IMO i expect it to be in the $10 (minimum) - $19 (maximum) Range

Anyway, I guess this will my first DLC purchase on PSN if not any other service.
now, i have to figure out a way to "purchase" this with using "my" card Details..