35 years ago, I used to race snow mobiles. At that time the "chrome" plated aluminum cylinders would not stand up to much severe punishment and there was no one in this area who could re-coat them. After having to replace several cylinders, I switched to cast iron as an economical alternative. I have no idea what type of chrome was being used at the time but the engines were made in Germany. It is too long ago to remember any of the details.
Wayne