FS Applejack actually was sold in the UK for a brief time on the site 'All The Cool Stuff'. I know this because I was actually able to obtain two :'3c
They seemed to sell out the day after I'd placed my order so they can't have had many to begin with. Stupidly, I sold my 2nd early on for a pathetic £30 - at the time, that was double what I paid so I was ok with it - now I regret selling her so much; not because I could have made more money, but rather because I have lots of fellow brony friends and I would have far rather they have her than some anon from ebay :(
The AJ I still have is actually still sealed; I'm constantly torn between keeping her in her box in case I'm ever desperate for money or breaking her out so she can be with my other FS ponies and not look so lonely!
I know they recently released a new FS Twilight (as a princess) and Pinkie Pie so hopefully the others will follow suit. I've also contacted several sites (The Entertainer, Argos, Debenhams, John Lewis) about their FS pony stock, but most shops only seem to have Rainbow Dash, Pinkie Pie, Rarity (who's also made a bit of a comeback!) and Luna.
Hasbro need to realise they're really missing an opportunity here!