Can we buy and repair parts for C12?

If we purchased a used wheel, is it possible to get parts like the PCB, proprietary chips and etc if it broke in the future?

Parts Yes.
PCB Yes as long as it is still being sold and not EOL.
Proprietary chips ? No.

Technically you have 1 year warranty of 2yrs if you’re in the EU. In that period you will get replacement parts as long as it is not physically damaged and and have manufacturing issue.