Not many people like them but I am a big fan of the
Schaller Trem-Stop. It mounts on the face of your guitar behind the tremolo. You can either use the supplied double stick pad or screws. You swing the
trem arm around backwards and it is a claw thing that grabs the arm. Holds it steady for tuning or keeping double stop bends in tune. It is not strong enough for detuning or staying in tune if you break a string however. That's fine with me though. I have 4 of them.