Katzkins will only sell through a retailer, but luckily they have a partnership with Chrysler/Jeep so you can not only purchase the kit through a dealership parts dept., but can customize and add options that would usually cost hundresds for free! I got mine from here:
http://www.moparsupercenter.com/katz...eather1pu.html
The heated seat kits were an eBay purchase; universal carbon-element kit, with TONS of modifications and splicing to get them to work on the rear seats. Definitely doable, just takes some time.