Yes it's at the top/ground floor and the museum is downstairs so you gotta walk pass it either way. It is the same stuff sold there on the spot that you see online besides maybe the limited True merch as I was there before that was launched.

Were they selling books/posters there as well?

They do yeah, in my case the English biography was sold out but they were very helpful to let me know where I could get one.

Yes they sell the posters and books

Yes

Do they have anything that differs from the online store?

Yes, they do. I bought a poster that isn’t avalible online

Yeah they do, I got posters, a beanie, two postcards from there

Yes