[ImperialCrown]

I have had 'clunk' noise issues with aftermarket bushings & went back to OEM. If the ball joints are worn, replace the arm assembly. If just the bushing is separated, it can be pressed into the existing arm.
The arm design is common, it has to control the up/down forces as well as the acceleration/braking forces. Hence the axial & radial support bushing configurations.

The rear bushing is 'captive'. Separation isn't really a dangerous condition. If anything, the 'clatter' over bumps of the arm as it comes to rest on the crossmember is annoying.
The rubber loses its bond to the steel shell because of corrosion.

Something seems wrong if this part has to be replaced almost annually. Even in the winter road salt areas, these should last about 5 years.