Herretts does not offer mesquite as an option for their grip materials. They will use your wood. For Roper grips on a square butt "N" frame they require (2) pieces 3-1/2" X 6" X 1".
Pictured is a mesquite plank I purchased today, it measures 5" X 24" X 1-1/8".
Where would you take a set of...