The Stock-and-Horn is treasure that can be obtained in Sly Cooper: Age of Thieves in the episode Braverobber. It is worth 233 coins and the time needed to reach the safehouse is nineteen seconds.
"The Stock-and-Horn has been a Scottish favorite for many years, with Slaigh MacCooper favoring this instrument over any other. This particular one was taken from an old rival of this from England who had intended on using it pull a prank on Slaigh."
It is located behind a mine field that has some flashlight guards nearby. Only Sly's Mascot Costume can be used to reach this treasure.