Spelter Promotional Clock for Herkimer Bank

This is a 4" tall 2" wide 6 3/4" long antique vintage Spelter promotional Advertising embossed Mantel Clock Coin bank from Herkimer National Bank Herkimer , N.Y. I bought this item at a garage sale. I would like to find out a little bit more about this item, for example, what year it might have been created, or a little information about Herkimer National Bank. Any information you have is appreciated, comments are welcome. Additionally, the man who sold it to me did not have a key to go with it so if anyone has any information on another way to open the coin bank then please let me know!