Square Enix have released a series of short minute-ish long videos highlighting a series of Samurai Costumes to be available for Lighting Returns: Final Fantasy XIII with pre-orders through different retailers in Japan. Some or potentially all of these may be eventually acquirable internationally.
Samurai Series Trailer
Shining Prince
Fuurinkazan
Flower of Battle
Shogun
Sohei Savior
Dark Samurai
Utsusemi
If none of these costumes appeal to you, as we have earlier seen from promotional footage/screenshots, there is a considerable selection of outfits for Lightning to wear as she goes to end the worlds “13 Days till Death” countdown.