I haven't had too much time to work on this lately, but I'm trying Son's method. I have soaked the handle in mineral oil and have been really surprised with how much it has come back to life. I will still probably need to apply some epoxy later on, but I am happy a new handle is not needed.
As for the blade:
Man, I have scrubbed the bejesus out of this thing with with some emory and cork with very minimal results. I tried some emory compound and a buffing wheel and got much better results. Most of the big black areas I first thought were patina(but were rust) have come off. However, there is some substantial pitting in at least 30 spots on the surface. This pitting is so deep, and the blade so thin that I don't think I can make them go away without totally ruining the knife.
I can't wait to finish the cosmetic refurb on this, put a good edge on it -and give it back to my boss. This thing has been in his wife's(also my boss) family for God knows how long(maybe a hundred years if Son is right)-and I am happy they will be able to use it again. Maybe for special occasions- for Thanksgiving or a Seder dinner.
I kinda think some knives may have a soul.............as cheesy as that sounds.