First-Person Deadzone Aiming

Hi, I’m trying to create deadzone aiming like in GoldenEye or Perfect Dark on N64, where you rotate the hand towards the crosshair within a deadzone, and when the crosshair leaves that deadzone the camera starts rotating. In GoldenEye at least, this is an oval-shaped deadzone as evidenced by the attached screenshot.

I’ve seen some tutorials on “Reids Channel” on YouTube, but they haven’t helped as the gun rotates in a very strange way when looking straight up and down, and doesn’t include hand rotation and forgoes the hand model (though I suspect it’s easy to apply the same rotation to the hand using IK).

Any help, somewhere good to start? Thanks!
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