I'm not sure if this will be of any help, but there is an English Heritage property called Witley Court at Great Witley, in Worcestershire. It is currently a magnificent ruin, but has an enormous fountain in the grounds, and attracts many visitors. If you google Witley Court, Worcestershire there is a telephone number, and someone may be able to help the Wall House. (Perhaps a Gatehouse for the Court?).
It's a bit late now, so I haven't looked, but there may be a website.
giraffe