How much does merchandise cost at Taylor Swift's Speak Now concerts?

I am going to one of her concerts here in the U.S. in a few weeks and
I wanted to know how much things like t-shirts an glow sticks cost
there. I've been to a Glee concert at that same arena that she's going
to be in in my city and t-shirts cost like $35. Is it different for
each artist or venue? Please be as specific as you can! Thanks :) .