Typically the dealers can't really negotiate too far from RRP for the vehicle alone. For example if you walked in to two dealerships after the SR you mention, with no options and no trade-in, and paid cash, they should really sell at the same amount. Or at least that's the way it *should* work.
The negotiation factors where flexibility can be introduced into the overall price would include:
* Accessories - maybe they could toss in some free or reduced stuff
* Trade-in valuation
* Finance deal (if not going cash)
Current Aus-wide deal for dual cab SR (tub though):
http://www3.toyota.com.au/hilux/offers/2016-Sep/190766$46,990 drive away
2016 SR HiRider -
<Thread>Factory Options: Premium bullbar, tub liner, tow pack
Additions: IPF900 spotlights + 20" LED bar, tint, TJM canopy