I have one that I just made for my own 1979 special. It is sweet, perfect, brand-new and never been ridden on. It mounts clean and simple, and without any of the stock mounts or hinges. It has the same type rubber bumpers that ride on the frame tubes as a stock seat.
It will not work with a stock tank. It requires a Sportster or similar peanut tank.
Price is $200, firm, plus whatever the actual shipping costs. If interested, PM me your email, and I will send pics, including pics of what it looks like with a Sportster tank.