I get a little mixed up with out going out and looking at my C, But if memory serves that is the touch control hydraulic temp sending unit. If that is the left side of the tractor while looking at it you have a Fast hitch equipped tractor that has the draw works connected to the lift arms on the "touch Control". Above the steering shaft while you are in the seat are two levers, moving one or the other swings two arm through an arc. this hydraulic unit had a gauge above the levers that ran to the hydraulic unit .
You can get the part from Stiener tractor online, and you can get better manuals from Jen sales online to. These manuals cover the original operators manuals and they have pictures of the controls and such