Our Head is made by Simpson Laurence (Lawrence?) out of Scotland. Other than after about 6 weeks when a non-stainless pin corroded, it has worked fine. One can't get parts for these anymore. I've searched around and even gone back to Simpson L and they can't help. Incidentally, that Head in 1981 retailed in Canada for about $450.00 whereas the basic Bryden went for $80.00. I have used my spare Joker valve and I really don't want to be without a spare valve. I've not found a valve that matches.Has anyone else faced this challenge?Has anyone replaced their Head, if so with what?Thanks,JohnTir Na Nog,Vancouver, BC