I would think your best chance might be to contact Sid Watson, he has moulds for the wings and he did have one for the hard top, but when I asked about it he was _extremely_ reluctant to get drawn in to the idea of making one due to the problems with fitting. By the time he had explained to me all the problems that could occur (too many differences in cockpit wide, windscreen angle, door sizes and opening etc) I lost interest in the idea and decided to stick with the soft top.
But if you could persuade him, and had a thick enough wallet to make it worth his while, I believe he would be the best bet, he made an incredible job of my wings so I have no doubt as to his abilities.