I have one, but I got it from Australia because I was having the same problem (finding one, then finding one at a decent price).
MPenguin: I'm not sure what you mean exactly. The one I have screws into the frame (wood or masonry) of the door. You have to drill three holes on either side and then there's a kind of cap with three holes that you attach to each side. You then wind the bar out until it touches the the edge inside each cap. I don't know what the upper weight limit is on these, but I do weighted pull ups for a total weight of over 90kg.
And you coming in to scold us all like some kind of sour-puss kindie assistant who favors olive cardigans and lemon drinks without sugar. -- Muzha Man
One sometimes gets the impression that the mere words "Socialism" and "Communism" draw towards them with magnetic force every fruit-juice drinker, nudist, sandal-wearer, sex-maniac, Quaker, "Nature Cure" quack, pacifist, and feminist in England. -- George Orwell