Chaim gives a wider list, but I suggested looking at r Soloveitchik, who was recognized by enough gedolim, some disagreeing, he was on moetses early on but then quit. Maybe he is not a Z in r Kooks sense, but he writes a lot about related issues. I would suggest this book: Community, Covenant and Commitment: Selected Letters and Communications, it had a number of letters on political issues so that you can see his shitah. I would also open one of his less political seforim for balance so that you get an idea of his lomdus.
