Does anybody know where I can find a wireless telephone extension that
carries the signal through the ring mains?

I want one to connect my sky HD in the living room without having to
install wiring. I don't want to use a standard DECT system as i
already have three devices running on 2.4GHz (router/telephones/video
sender).

I have seen some literature on the net about them (e.g. Easy Jack) but
nobody that actually sells them!

Many thanks, Miguel