Flat panel radiators

onlineid

Need to replace four radiators and keen to go for slimline, flat panel look. Does anyone know where I can get these from without it costing thousands? Looked at B&Q, Wickes etc but no luck. I've also got a room almost 10m x 8m. I need also replace the radiator in here which is 2m long and need one with obviously a large output. Any idea what I should be looking for? I did have two radiators in here and have just removed one as never really had the need to turn it on and have triple glazing so hoping the one should be fine.