I have a 68 S and the gas heater exhaust is rusted a bit and need replacement. I have the down pipe and muffler, but lack the exhaust pipe. I want to return them to 100% stock appearance. Three questions;

1. what is the stock color, they are grey primer now?
2. are they undercoated?
3. where can I get an exhaust pipe, or do I have to make one?

Thank you for the help