Great find! I would suggest leaving the coating on. If it is A2, the coating will aid in keeping the rust away. If it is INFI, well, I'd still keep the coating on it. Those scratches are just love marks. Have fun using it and don't worry if you add a new mark along the way.
Some folks have used a bluing pen to test the edge in order to see if the steel is INFI or A2. INFI will not absorbe the bluing, but A2 will. The only other way is to send it in to the Busse Shop and request that the Boss himself check it out.
As far as cleaning up the handles, a nylon bristle brush and some dish detergent should do the trick. The Micarta is very tough and can be bead blasted, but again, I'd just leave it as close to original as possible. Scrub it up and USE IT!
Enjoy your classic find & Welcome to the Busse forum!
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