> If I take it to be a FR no such code in current or obsolete.  Same for F8
> and FB. But isnt that sticker too small for a UN country code marker?
> 

After about an hour's google research, I have determined that it is a
novelty sticker for "Folly Beach" <http://tinyurl.com/b525t>,
referring to Folly Beach, South Carolina, a popular surfing
destination on the east coast. Seems to fit in the same general calss
as the other stickers.