Has anyone seen this specific style of cab or gauge lamp?

I'd like to know more about the configuration of the top piece.

To start, I'm including this cropped Porter photo for reference.


I suspect Porter didn't actually make this style of lamp but, instead, was made by one of their suppliers. This style of lamp was common Porter locomotives in the early 1900's.

After 15 years of searching, I recently acquired the lamp shown below on the left.
My 1904 Porter still had the original lamp base shown below on the right.

Unfortunately, both pieces are full of stress cracks.

There are no manufacture's markings on the lamp.

The globe would've originally been painted red on the inside, leaving a small tear drop opening to illuminate the pressure gauge.

The large hole in the top makes me think something is missing or the top was modified.

If you are looking for a replacement globe I would suggest finding a local glass blower.

My guess: The missing piece was likely a small brass chimney cap so the lamp would draft but keep any wind or debris out. You can see it in the Porter photo.