Can I purchase just an idler / tension pulley sleeve?

I just installed a UPD pulley set and right away notice a slight wobble in the the serpentine pulley. I'm now paranoid that the wobble will eventually wear the pulley down prematurely. All other pulleys are stock and have zero wobble / movement.
There's only two things that I can think of that would cause the wobble, (1) the pulley is slightly off / imbalanced, or (2) the pulley sleeve is messed-up.
While the sleeve visually looks more or less perfect, if it's cheap, I'd like to just replace it. Does Mercedes sell just the pulley sleeve? I've only found it sold as a set with the stock pulleys (~$500).
I just installed a UPD pulley set and right away notice a slight wobble in the the serpentine pulley. I'm now paranoid that the wobble will eventually wear the pulley down prematurely. All other pulleys are stock and have zero wobble / movement.
There's only two things that I can think of that would cause the wobble, (1) the pulley is slightly off / imbalanced, or (2) the pulley sleeve is messed-up.
While the sleeve visually looks more or less perfect, if it's cheap, I'd like to just replace it. Does Mercedes sell just the pulley sleeve? I've only found it sold as a set with the stock pulleys (~$500).


