Double din with touch screen, (could even go with integrated Gps)
din adapter, stalk adapter,
Then depending if you want crazy bass or just a good all round sound either:
A pair of slim line subs under the seats with an amp mounted under the centre cubby,
One big sub and amp in the boot ( plus a quick plug so you can remove in seconds )
Or get hold of the original style sub in tailgate but then you will need a small amp hidden behind the trim in the boot to power it as it won't run off an aftermarket head unit.
In a Range Rover there is a lot of interference so buy the cables with the best shielding you can afford and run the power down he opposite side of the car!
I have always found Pioneer to be the best with Alpine a close second for high class audio and both can be tuned with 3 presets for whatever kind of music you listen too,