Sorry, I don't know if the list is still open, I know a while ago they put it on "hold", but I can check and see if I can find out anything. As far as a special discount, I'm not sure if there was one. My armor was pretty expensive. I think the perk was just that 501st members were able to get their hands on it. I'll know for sure if there was a discount once they release the public price
Anyway, I'll see if I can find out anything about the list.