"Bonzer mate, she's a true blue phrase if I've ever seen one."
Fair dinkum means truly, honestly or on the level. And just so you don't get confused, "fair suck" or "fair suck the Saveloy" is related to "fair enough" rather than "fair dinkum." I have no idea what its etymology could possibly be.
Bonzer means excellent in the way Bill and Ted of Bill and Ted's Excellent Adventure would express that word.