At my Wits END

Can anyone please advise ? I bought a TD5 ES 2002 3 weeks ago after the 1st week the radio stopped working, the next day the immobiliser would not switch off ,telephoned local landrover dealer and after showing proof of ownership I was given the code to unlock the car and turn the immobiliser off which worked fine. Booked car into dealer who said the problem was the key , we had a new key made and still it would not work dealer now after working on it for 10 hours is convinced it is the B.C.U. not the E.C.U. they have searched the complete Landrover Database and no one has this part in stock the car has been in the garage for 2 weeks
and I have been informed today that Landrover do not expect to take delivery of these parts until 16th of October 2005 !!!
If anyone knows anywhere that I can obtain the part I would be pleased to know

Did you buy your car from a dealer ????