It's unlikely that the exact GVM of your vehicle would be listed in any records within Toyota Australia as it's a grey import.
The LJ70RV was sold new in Australia The GVM of the LJ70RV is 2210kg.
Your's I gather is the LJ71G. I can't imagine that the GVM would be much different (if any) from the LJ70RV. It would not be unreasonable to base the brake test on the GVM of the LJ70RV, if you can convince the engineering signatory that the LJ71G and LJ70RV are equivalent.