It's not often a console this rare goes up for grabs, and privately, too, it's more often that larger auction companies get their hands on this, but not this time. This is a personal item, belonging to John Numbers, the very person who won this incredible collector's item back in 2015.
In the summer of 2015, Nintendo held a special competitive gaming event called "Nintendo World Championships 2015" during E3. It marked the revival of Nintendo's historic gaming tournament in 1990 while celebrating retro and upcoming Nintendo games.
Competitors had to complete challenges on the Nintendo 3DS, but with a focus on retro games, mostly NES. These mini-challenges in games such as Super Mario Bros, The Legend of Zelda, Metroid and ExciteBike would consist of finishing levels quickly, or defeating bosses as quickly as possible or collecting certain items, or surviving for the longest etc.

Well, the winner of that challenge competition was John, and although he has held this incredible gaming tome for over ten years, it's time for him to let it go. In John's words, this is a "national treasure" and has only "been opened a few times", making it an incredibly good condition collector's item.
More specifically, this is a black Nintendo 3DSXL signed by Shigeru Miyamoto himself; it comes boxed, features some exclusive cards of John himself that were made by Walter Day back when the championships had concluded. Though the trophy itself is kept by John and will not be a part of the auction.
As of writing this news article, the bidding has begun on eBay, and the current winning bid is at $21,000, a mighty price for a mighty console, and as there are over 6 days left, this will likely increase throughout next week. John has mentioned he will not ship internationally, and may even hand-deliver it himself once sold. Take a look at the listing on eBay here.