The ignition lock housing in my '83 300CD was replaced/repaired(!?!) by the PO and is currently held in place by a hose clamp.

I can turn the switch and start my car with a flat-bladed screwdriver - or I can remove the key and leave the engine running.

So, in addition to a new ignition lock housing, what do I need and how do I make them match up to my currently matching and functioning door and trunk locks?

The ignition parts list at Fastlane include the housing, the cylinder, the switch and the cover w/ some trim accessories.

Do I order a new lock housing for under the dash, then order a new lock cylinder from the dealer with the VIN to have the keys match? Can the dealer VIN records go back that far? (I can't use the online M-B system epc.startekinfo, but have to go manually due to the age of the car). I presume since all the other keys work correctly, including the glove box, that they are original.

Can I get a new ignition cylinder re-cut to match an existing key, or do I have to go the other way and get the doors and trunk re-cut to match the new ignition cylinder?

I'm not a fan of multiple keys on the key chain, so I don't like the idea of separate door and ignition keys. I've also read the advice on getting a junkyard replacement housing, but due to the problems caused if/when they fail (key stuck in ignition/won't turn - correct? And that wouldn't solve my screwdriver problem) I'm inclined to go with a new replacement housing for the $150 or so estimated cost and fix the cylinder with an actual key.

Any recent experience with keys of this vintage from the dealer? Or from locksmiths on cutting new door or ignition keys or cylinders?