Rams Head Antiques has dated this piece to the 1960s.
The silvered, textured dial has baton markers and a date aperture. The stainless steel screw back bears the Constellation monogram. The movement is housed in a very handsome gold plated case which is 36mm wide.

The gold plating is in superb order and the movement is very clean and keeping excellent time. The date is also changing correctly. The strap and buckle are also in excellent order but are not original to the watch.
Rams Head Antiques has dated this piece to the 1960s.
You can view the stock and full dealer information on the Rams Head Antiques Profile Page