Thanks for the reply. From my enquiries with the local Pedders dealer, the Pedders kits is the real deal, with welded on diff lamination, welded on rear coil tower brace, upgraded springs and shocks, as well as full on certification. Even then, the pedders kit only get you upto 3300kg GVM anyway.I'd say almost certainly not and I'd also say that Pedders are one of those in the sights of the TMR for providing a GVM upgrade without doing anything to upgrade the axles apart from writing some bigger numbers on a piece of paper.. Expect any GVM upgrade that complies with that notice to cost a lot.
There are other issues that contribute to GVM capacity other than the carrying capacity of the axles such as braking capacity and anti sway capacity. Expect companies to offer upgrades up to the 3300kg limit at more reasonable prices but above that will become dearer than it already is.
I'm pretty sure Lovels are even dearer and you still only get springs, shocks and a certification plate fixed to the body.
The Pedders kit might be my best option, and is likely best to be done sooner rather than later. Either way it looks to me like the Pedders kit would likely be fine under the new regulations.