Rust in chrome, if is not deep, is easily removed with WD40 and "steel wool" -or whatever the correct name is-
Has anybody ever heard about what a "white elephant" is?
A "White elephant" is a term to describe something extremely rare and valuable, but at the same time, extremely costly to keep. It is like inheriting a Picasso's paint. Feeling lucky at the beginning, it may easily ruin you for the cost of insurance, environment adaption of your house etc.
This guy must have been lucky to find this bike, but at the same time, it may have become a "white elephant" for him. Restoring it to original condition, if only for replacing parts, will probe costly. Somebody has even suggested replacing the sidecovers for replica, for fear of them being stolen.
Would you be happy to score a bike like this, and then not enjoying it for fear of being stolen?
I would say, sell the bike at a big, big profit, and with the proceeds, buy another bike not so coveted so you will enjoy it more, and spend the remaining money in yourself, or if you decide to keep the bike, keep the broken sidecover, the broken seat, keep everything, clean and polish a little here and there, and run the hell out of it, and if someday you discover your bike has been stolen, you won't feel that you have been stolen a fortune, a white elephant.
You will feel you have been stolen $100. That's what the bike was worth when it was just a piece of junk in somebody's barn.