http://wheelflip.com/services/
These guys do good work from what I read online. I also took them a 10" wheel I have to shave 5mm off to fit in the ls.
If the wheel can be machine flat and true to begin with, it can be shaved down but you do need the right equipment and have it all aligned. Wheel work is all they do, when others say it can't be done, these guys tackle it, so I'm sure they have the right set up to do the work right.
I was even considering getting some staggered wheels that had the right offset but wrong bolt pattern and just having these guys re-drill them to the right bolt pattern.