If the lock jams completely, you will have to destroy things to get it apart so fixing soon is vital.

To take it apart the key must be turned to the 2 position so the cross bolt can be removed from what I recall. I have a spare column for my 97 SL320 that would not allow the key to turn all the way to the 2 position. Eventually I got it apart and the column locking parts had worn and jammed.

97 has a RFID chip in the key and an antenna ring around the lock cylinder, this is called DAS X.

If you replace with a lock / key from another car, you could get another antenna plug it into the small black anti theft box behind the instrument column, tape an old key in the ring and leave the whole mess behind the instrument cluster. ( 210 820 32 26 ? for the anti theft box ) Also, the boxes are locked to the engine computer so they must match.

Or, if you use a flip key, drive out the roll pin and put the new key bit in the old housing so you retain the proper RFID chip. ( the old fixed head key will no longer work in the lock but would have the proper chip )