As for the damaged lens, that is a very simple fix, if you are competent with camera repair it would be no trouble. It is a unique presentation, but is is a common degradation of the lens cement. The cement used is Canada balsam, a refined tree sap that like all organic material ages. After removing the front assembly the individual lenses would likely separate with light force with a fingernail in the gap or warming the whole thing in water. Be sure to draw a line across both lenses on the ground edge to reposition them. After removing the balsam using solvents it can easily be re cemented. Balsam could probably be bought from optics suppliers or maybe even an artists supply house.
After heating the Balsam to flow at a good consistency and the two lenses are warmed so it will not gel up, put a good amount on the lens surface that is concave. be sure there are no bubbles and care fully place the lens on to making sure the pencil marks line up. As you let it go down the Balsam will flow out and when it is firmly seated, tape the element to keep it in place to solidify.
clean up the excess and replace in the barrel and it will be as good as when it came out of the factory. With less yellowing it should also be faster then before.