I just got off the phone when I posted this and the info is what the dealership here local told me. Mine polished are what I posted with a 50 dollar core charge. He said the black were more and since I didn`t have a core it would be a extra 50 per tire. Don`t know why they would lie to me..
These quotes are from a GM dealership in town.. Might be cheaper somewhere else, I can`t say..
2013 Red ZL1 Auto modded
2015 C7 ZO6 Luguna Blue stock