I found this at screwfix. This screened socket has just about everything one will need in one place.
It has the two satellite cable feeds allowing me to feed a sky + box. It has an FM and normal RF TV socket and also has a return socket. That means you can take the feed out the back of a sky box and distribute it around the ship. Finally, it has the telephone socket in there too.
I don't yet have to worry about how to distribute at the moment, I just need to wire each room with a full set of cables and worry about what to send down them later. I may need to order more cable!