You really need to add more photos, side shot and front. If there are barn doors open them. Interested but need more photos. Some of these old brass ones had pieces that attached and I can't see if this is the case on this one but all pieces need to be there and more photos can help.
I do believe this is a 2 or 3 piece unit, please remove the pieces if you can and provide more photos. Someone will be pretty disappointed if a part is missing as they are nearly impossible to find. It is an oldie!