Mass accessory purchase - big trip

Any comments you have on the following would be much appreciated:
We are planning an around Australia trip in our 1990 Pajeo EXE Turbo Diesel Wagon and we have to accessorise our vehicle
with the following:

Roof rack, Fridge, Air compressor, Cargo barrier, Hand winch, set of new AT tyres, fitout of Pajero with sliding draws/storage, and other less costly items too.

We are planning to go to either the Dubbo or the Sydney 4x4 shows in late June.
Does anyone have any comments about which show provide us with the best value as far as buying all this stuff goes (Dubbo show is much closer to us)?
Perhaps wed get more one on one attention at Dubbo??

Also what sort of bulk discounts do you think we could expect if spending say $5,000 plus on all this?

As far as tyres go does the Bridgrestone Dueler AT D693 sound OK? The Big Red air compressor is also on the short list.
The storage fitout will cover the whole Pajero rear we think. Is it usual to remove the rear seat altogether here? And how much is this likely to cost - whos the best supplier?

Thanks in advance for your insights.
Best regards
Gary