I just had this happen to me. I couldn't justify just replacing the single bushing. To me it made WAY more sense to swap out the entire control arm. My reasoning:
Yes replacing just the bushing is cheaper...I got my new control arm for $75 from rock auto and used a 5% off coupon from retailmenot.com. My car is a 2002 with 120K on the clock. The other bushing including the ball joint are just as pron to go out, with winter coming it was a no brainer to me.
For $50 more I got a new control arm, the other bushing, and a fresh ball joint. Now if I went the other rout, what if the rear bushing went out on my way to work at 5am in the dead middle of winter. The extra cost was worth the peace of mind for me, my car is my lifeline..no car no work = NO MONEY lol
