Unknown Vintage Aircraft Instrument? Optical Sight?

[AirMechanic]

Does anyone know what this item is? I am fairly sure it is aviation related, but I’m not sure if it is military, or how old it is (I believe WWII-Vietnam era).

 

It is 4 3/8” length x 2 9/16” width, and is matte black in color (like many instrument panels), with the faint remnants of a white round stamp on the top of the flip up door. On the front top is a clip with a white sighting line(?), held in place by a slotted adjustment screw that rotates the gears on the back. These gears controls the spiral shape aperature on the larger of the two round optical devices(?) on the back.

 

The front flip up door opens up to access the two bulbs inside (marked T53 on each bulb base). The back has a recessed channel with a rubber o-ring gasket to seal this item to whatever it was mounted to (most likely an instrument panel).

 

As far as the two optical devices(?), one has a V-shaped cross hair with a dot in the center and a small plus sign above it when a light is shined through from the back. The other device has an adjustable spiral shaped aperature that changes size when the gears are rotated. Pinpoint size light shines through at the 6 lines of the spiral and at the center.

 

Does anybody know what this is, how old it is, and what aircraft it came off of (if military/aviation related)? Any help is appreciated!

[phantomfixer]

My first thought is part of a gunsight or HUD

 

edit...part of MK 18 gunsight

 

https://www.ibiblio.org/hyperwar/USN/ref/AirGunnery/MARK18GS.html

[AirMechanic]

I think you got it. Thanks for the info!