That is common navigation for a steering cable... I can't believe that the wheel was easy to turn w/ that much damage. Most of the time they get sticky over a few seasons w/o damage. I'm sure you'll see an improvement.
Look at rexmar.com for prices on cables and new assemblies. If what you have now is a rotary system and older, a new one of any type might take some drilling in the dash.
The cable is not difficult to replace, and even if you replace the whole assy., it shouldn't be over your head.