where can i get a home guard battle dress jacket?

Would anyone happen to know where i can get a HOME GUARD battle dress jacket, i live in the uk and all the shops i've ben in touch with haven't got one let alone know where to find one, i want the 1940 type with concealed buttons, the woolen type. doesn't matter about size etc as i'd like to frame it and pop it on my wall, would also like to track down the cap they wore too.
many thanks for any help anyone can give
daniel