Help Identify Iron Bell

I have an iron bell supposedly from a UP train, can anyone help identify what engine this may have come from or at least an approx age? The pneumatic piston has some numbers on it. One side says TRANS.TN DEVICES CORP and the other side says 8-163. Any ideas?
Thanks
Eric

ADMIN NOTE:

Moving this to General Discussion: Locomotives, Rolling Stock, and Equipment.

Friendly advice. Photos would help. Easier to identify an item when you can see it. We can take a link to a flickr, photobucket, or google photos image. If the photo is smaller than 800x800 pixels, we can turn it into an image here in the thread.

I found a post showing almost the same bell and striker, the only difference is mine is iron. Does anyone know these bells and when Transportation Devices Corp started using this same design but in iron?
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Transportation Devices Corp was in Indianapolis, Ind they may have merged into other company, they were listed in 1922 and 1935 railway directories.
my guess is they switched from Brass to Iron during World War II.

Here is a link to the Car and Locomotive Cyclopedia by Simmons-Boardman.

I'd consider going to archive.org as well to see what else is available in digital libraries...

EMD made the change from brass bells to cast iron in the mid to late 1970's - I did the sound testing that showed they created a similar sound level, although not as pleasant a ring, as the brass bell. The reason was to cut down on the theft of bells for their scrap value as well as to make a production cost savings.

Dave