I've been looking into this for the last week or two as its something I will be considering in the new year. I've been looking at Land Rover Discovery 3's as I too was under the impression that the X5 couldn't be done.......but

There's an X5 with cre can status on donedeal at the moment for sale!

My understanding is it's easier to buy the 5 seater of whatever jeep your looking at as the rear 2 will not have to be removed then.

The shogun is an option too but not many of them in my police range.