Cool story, maybe paint it battleship gray (Rustoleum Hammered Gray looks good) to honor its place in history. Be careful with that sticker so you don't loose it or paint over it!
Yeah, my guess is someone was beating downwards... bam, bam, bam, crack, oops...
You can probably grind it smooth and blend it in. I've used JB Weld as kind of "vise bondo" if you want to do any touch-up of little dents or holes.
You can contact the guy @
http://wiltonviseparts.net/ to see about making a new set of proper jaws. I forgot his username here on the forum. They aren't cheap but they will be better than new.
Alternatively if you want softer jaws you can make your own from Aluminum, Brass, or Bronze...