Eastwood Company has it on their web site for $99. + shipping. I recently purchased a set of Team III Cobra wheels for my Mach 1 and am thinking about using it for the polished inner rim. If it lasts as long as claimed (2-3 years), I'll be happy with that. There is a video on the Zoop Seal site to show how to apply the product.
If it works (and I'd sure like to talk to someone who has used it), it is certainly cheaper than paying for clear coating the inside of the rims.