Brand New HTC One X on O2 !

i have a brand new HTC One X for sale still boxed never opened with receipt.. i got the phone as an early upgrade which i dont need.. please serious buyers only phone is currently priced at 450 so i am being fairly resonable asking for 350 ... phone is on O2 and is fresh off the shelf contact me via telephone or email... please attatch email address so i can get back to you.. thanks joel