I had been looking for an unlined Gore-Tex parka
If you do go with GoreTex, or another membrane type product, you actually want some kind of liner, even it it's just a light mesh or something like that. The membrane can be snagged easily if there isn't a liner, and can tear. I now have a rain jacket without an insulating liner, but, it does have a light nylon mesh that keeps anything from contacting the GoreTex membrane that is applied to the inside of the outer layer of jacket. It's in my car kit at the moment, but, I think it's from Pac-Tec.
The reason I mention it, is I ruined a jacket without a liner when I wore it over a fleece that had a couple exposed zippers. Then I put my backpack on top of everything and by the end of the hike, the zippers rubbing against the membrane had torn it up.