I made this same thread years ago and I'm going to do it again now. I think it's been long enough, I think it has existed long enough that everyone should be allowed to have it now. Put it on the cash shop, you'll make decent money out of it, I guarantee it. I don't think its fair to keep it locked behind contest wins or promotionals considering that you've done it to the Final Fantasy 13 Gear and hairstyle by the way.
Yeah I was one of the people that were actually playing way back when you did the FF13 crossover event. I EARNED those rewards and then you decided to put them on cash shop and make them far far less special. You did it to the FF10 stuff too. So I think it's only fair by all rights that you put Modern Aesthetics - Strife on the cash shop too.
Edit: It would be even better to see it be earnable in game one way or another. A couple people said wolf marks, a couple others said Gold Saucer. I wouldn't mind seeing it as a treasure map reward. Raid, trial, or Dungeon would be fine too. But I imagine you would want it to be themed after something FF7.