Are you talking about a box for just the silver quarter sets or a box that is designed to hold all ten full silver proof sets? Do all ten years fit in the box? I ask this because they are probably after market boxes. Back in 1999 when the
State Quarter sets first came out the Mint DID offer a box to hold the full ten years of sets, and they sold a bunch of them. But at that time the five quarter silver set was not being sold separately. So it would be a box for the CLAD five coin proof sets, or the full clad or silver proof sets. Then after selling all those boxes the first year they stopped offering it. Which was just as well because once the President dollars were added to the proof sets in 2007 the full ten years of proof sets would no longer fit in the box.