Thanks Don Kee, that would be nice if it was. It's the only number that seems to fit the bill.
Matt, now all I need is to identify the kerb weight!
I've tried that Bobplum, but thanks anyway.
Spruce has suggested that the payload may be around 1300 kg, but he pointed out that it depends on a number of variables.
I was informed that the payload should be displayed on this plate somewhere, but perhaps it's revealed only through calculating the gross/kerb weight differential.
So, I need the kerb weight, I guess.