Elena's hair is easy to replicate on your own (a side ponytail with either flowers or a headpiece). Target has red and orange rose hair clips that work perfectly, and Spirit Halloween sells a metal Elena "tiara" headband.
There are commercials for it on The Disney Channel every 5 seconds, but it does say Disneyland. No guarantee, but I imagine something like this will be available at MK soon, especially if it's a hit in DL. It was the same with the Frozen hairstyles. Our daughter has the Elena Disney Parks dress (and fully believes Elena sent it to her). I'm hoping they will do an Elena pony with pixie dust for our late Feb/early Mar trip. I do have the Elena headband, earrings, and bracelet for her.