No maker's mark on silver flask

My father purchased this silver flask in 1980. The note on envelope says “tested pure silver possible 1870-1875”. He paid $20 at the time. The flask is 4 inches long an 2 inches wide. I don’t know if the markings on it are a maker’s mark or just an engraving. Any information would be greatly appreciated.
Thank you,

Hi there and thanks for joining us. The writing is custom engraving and not related to the maker. I don’t see any maker or purity marks. Try lookin g on the bottom or perhaps on the inside of the lid for other marks.


Uncle Vic