This brochure below is from the Japanese company Whitehouse, who are making replicas of Jim Goose's bike, including the fairings, the stickers, the helmet - the whole deal as far as I can tell. Unfortunately I don't know much more than what is on the brochure below. I do know that quite a few people have tried to contact them from outside of Japan, but have not received a response. I think the people at the company only speak Japanese, and unfortunately most people have tried to contact them in English, hence the lack of response. One alternative would be to try sending an email over to George Harrod. He's an Australian currently running a business out of Japan dealing primarily in Kawasaki parts (both original and replica). He has mentioned that he would be happy to try and help out anyone trying to obtain the various Whitehouse items as well.
While you're checking out Mad Max sites from Japan, you should also definitely check out the MFP clothing branch.