In reply to Russell Lovett:
There are several spots near Bellingham where you get big skies from the car, probably as dark as Kielder, but perhaps not as far for you.
The ridgeline just north of Shitlington has road access.
The B6320 that runs north out of Bellingham has several clear high points.
A bit further North, The B road (sorry don't know the number) that runs west from the A68 towards Padon Hill should also be good.
Steve