Just saw this in my local GameStation in Liverpool. Cheapest I can find online is over £30. Not sure if its pre-owned as it just has a sale price on. It has a bit of sticky tape on the side of the box and the DLC code inside the box worked so I think its new.
Not sure if this is Nation Wide but am would guess it is. Am not sure if this deal is for PC and Xbox 360 as the store I was in only had PS3.