When we were there for Halloween a couple of yrs ago they had lots of stuff for sale everywhere. Some specific stuff near rides. Like a HM t-shirt near the HM. Those could also be purchased at the emporium.
Unfortunately, they ran out of t-shirts before we got to the store. That was probably because we were at the last party that yr. I would guess it's a safe bet that you'll have a good selection from which to choose. Since we'll be there on the 9th I hope we
ll get a nice swearshirt or two as well.