They don't have a published award chart - well not for their own metal anyway. If you dig around on their website they talk about using a "dynamic pricing" system, which one would assume means the price changes depending upon load, route, time of year, etc.
That said, there do seem to be some "standard" prices that sit behind their "dynamic pricing" engine. 55k for MEL/SYD-Europe in J appears to be the "standard" price for this award - only very rarely have I seen it available, but at a higher price. Pretty sure I've seen a variety of different prices for Y, though. And it is a bargain, as you say: I cashed in 55k MR points last year to fly CDG-xKUL-MEL in J on MH, and while not the best J product around, it's perfectly acceptable - and amazing "value".