The alarm that I have used is made by rclick it comes with alarm blippers that have flick out keys like modern cars. Mine looks just like my 13 plate golf's blipper (they supply the correct key blanks which you take to the key cutters {they charged me £5 to cut both} plus they also supply them with landrover badges). The alarm will also add remote start if you want that and has dozens of options for other things like lighting up the side lights for 30 seconds when you press lock or unlock etc
Costs:
£71.95 for the alarm with 4 door central locking interface, ultrasonics, siren, led, remote start and two blippers.
Rightclick
£18.95 for the window roll up module (connects the alarm to the windows)
£50.00 for 2 window kit from ebay (or £100 for 4)
£6.00 for a 6 way auxiliary fuse box
£50 for a safari rear door replacement locking mechanism with central locking bar
You can ignore the last entry if you don't want the safari door included.
You can ignore the window roll up module and windows if you don't want the windows.
You can ignore the aux fuse box if you are happy for a load of in-line fuses.