The C and K chassis are well known to get super sloppy at the steering gear box once they have a substantial amount of mileage on them. They of course have the lash adjustment that takes out the slop but even it can only fix so much wear and tear on the gear box. The slop comes from engagement between the input and output shafts of the gear box. Once the steering column/shafts are ruled out and they tend to have their own problems as well and can cause slop too then it usually ends up being the gear box.
You get a 200k C or K chassis that has had no front end work done on it you can almost always plan on a full front suspension rebuild (Tie rods, idler and pitman arm, control arm bushings, sway bar bushings, upper and lower ball joints and stablizer link kits) along with a new/reman steering gear box and steering column and shaft parts too. Not too ridiculous if it can be done DIY at home but can really rack up a bill if a shop has to be paid labor and parts markup.