After I posted I started thinking I really only need one axis of gimble. I don't mind having a bit of pitch but it would be good to get rid of the roll. Also, I would like to have a high damping rate, probably a fluid damper would be best rather than just friction plates. I don't like the stabilized gyro mounts because they don't look like they would stand up to immersion and a water proof one would be out of my budget. A simple gravity stabilized roll mount should be fairly easy to come up with.