Driver door lock very sticky!

[Pickledjudge]

Hi! I have a 2008 Polo hatchback with central locking by key. The driver door barrel is extremely sticky, so much that I have to use passenger lock. It is clearly either worn or very dirty. I have a few queries. 1. Can I swap the barrel with passenger door? 2. I don't really want a different key so can it be cleaned or repaired? 3. Can you actually buy a new barrel that works with existing key?

[amer6R]

clean+ lube