Mexican Coat of Arms Bell

Everyone,

I purchased this bell from a gentleman from a show the other day. He was selling German WWII items and this bell. All he could tell me is it was much older than WWII. The nice patina and the design of it had me intrigued and I was able to purchase it for $25.

I believe the eagle on the top portion of the bell is the Mexican Coat of Arms from 1823-1843. I'm not sure if or what saint that might be on the first picture. I also am not familiar with what looks like either a 1181 or a IISI on the other side. There are also other designs on the bell but it is hard to make out exactly what they are.

I would like to know if anyone can provide me with any information on what this bell may represent. Am I correct with the Coat of Arms? If so, does the bell actually date to that time? Does anyone know what the other details of the bell may represent.

I am also wondering is this bell may be of military origin.

Any feedback or information anyone may provide would be greatly appreciated.