Steering column replacement / spear replaceable or not?

You would replace the entire column. The most common failure is the pivots crack so that even if you managed to take it apart the replacement parts would be very loose or even come apart because of the damage. As such it's much better to just replace the entire column. Then it is more or less plug and play. You would swap the key cylinder over to the one you have so you didn't need to deal with different keys. The first image is the column torn down, the red circled items are the parts that commonly fail in the tilt section. To replace them requires the parts as well as the press that is used to assemble them, and that is if the case isn't cracked. To swap the complete column is easier. You remove the instrument cluster to access the two upper bolts. You have to be very careful with those columns though, They are assembled with plastic injected into holes to secure the shafts and they can be damaged if dropped. To remove the column, you remove the trim around the column, remove the air bag and steering wheel. Then you use the key and release pin to remove the lock cylinder and the immobilizer unit. Those get swapped to the replacement once it's in the vehicle.