do you mean the metal face surround of the key entry point ?
If I was you would see if you can get a second hand lock from a scrappy, some are happy to sell individual locks without buying the set.
What I would do is then strip each lock and take the locking wafers and any other required components from your old lock and put them into the new lock, this is a very careful procedure that requires skill and patience else if you slip with any of those wafers you will not know which goes where and your key will no longer open your lock.
failing scrappy try ebay or something, perhaps even another member may have the parts you need lay about in their garage ^^
Alternative is swap the parts from your passenger lock and then delock the passenger side.
As for outright swapping of passenger to driver side lock, I am not sure if it works or not, never had to do this.
Be aware that when stripping locks on german vehicles, there is a part within the lock under the rear paddle that may already be snapped, and when taking it apart it will not go back together in working condition until you have a new part, the part i call the crown.
After pulling the lock out look through the gap in the side and see if the crown is broken, the spring attaches to it so you should not have a problem seeing if the crown is fractured, sometimes even when they are broken the lock may still work, until its stripped and the broken crown crumbles to dust.
it would always be better to not have to mess with both your door locks, so go for the option that leaves the passenger side untouched imho.