Okay, so...no guarantees or anything, just feeling people out on this, but:
Who would want someone to buy the Premium or Elite dice for them at the con?
Yes, I'm maybe volunteering for this but I also don't want to be the guy who walks into the booth and buys out everything they have because I'm muling for people. :p That doesn't feel right.
On the other hand, each purchase at the booth is an increased chance to play Mistborn with Brandon Sanderson. So, not entirely unselfish here.
Again, trying to get an idea of how many people are interested.