Well to be fair, they are sold into industrial applications as well. Imagine the value of being able to install a sleeve on a downed piece of production machinery when making a custom replacement part would take weeks. Don’t know where the first application was. I first learned of them ca. late 70s perhaps, when I was a machine designer. SKF, patented. Surely by now the quality varies but IDK.

I would want a sleeve made of hardened alloy steel, or even one with a titanium nitride coating. I can’t believe SKF would make theirs out of soft steel. I do know that the life would vary wildly with the choice of material. Surface finish would be crucial too.

If a new balancer was impossible to source and I was working on a car I valued, and all I could get was a sleeve of unknown quality, I might even send it out for nitriding.

 

In this case a harmonic balancer is still available.

 

True….new balancer would have been best but I couldnt wait on it to get here. Thankfully mine wasnt to bad and so far not leaking.
A new one maybe in my future.