I'm wondering the same thing and having the same problem. I have factory half doors with the sliding glass uppers. My soft top is practically brand new, but the skins on the upper half doors look like the originals; they're faded, there's a small cut on the driver's side, and they leak a bit when it rains (coming from the window/glass frame, the doors themselves appear to have new weather stripping). But I can't find replacement skins anywhere! Everywhere I've looked appears to be the entire upper half door, but my glass and the frame is fine, I just want new skins. They're more expensive than just buying used full doors!