I bought an wireless rf sender.It works with sky and sky + not tried it with ntl only cost 30 quid and comes with red eye sender too
They do not have that model now but they have similar for 40-50 quid
Argos has an all in one solution well cheap
http://www.argos.co.uk/webapp/wcs/st...lickfrom=image (but it says remote does not work)
Bit more expensive
http://www.argos.co.uk/webapp/wcs/st...lickfrom=image the beauty with argos of course is if it does not work you take it back
Cheapest option then maybe would be cheap argos sender and a remote sender from redremote