Hi. My central heating flow and return pipes run up the surface of the living room wall into the bathroom upstairs. I'd like to add another radiator in the living room and thought I could lose most of the pipework by getting a vertical radiator with top and bottom entry valves. The ones I've looked at all seem to have their valves at the bottom so I'm wondering if they're even available? And if they are, is 2000mm x 500mm a regular size? Thanks.