They do.
Yes, the staff is very professional and helpful. Call them.
I have seen Marc Chagall posters, postcards and books. Merchandise changes during the year. Suggest you call the store before you go. There is a wonderful Chagall glass mosiac that you must not miss in the museum. Also, if you have a chance, visit the Shirley Ryan Abilitylab. They have a Chagall large tapestry.
Not sure about Chagall specifically; they do sell repros. Call them, they're very helpful.
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