The .69 cal. bullet is about 1.76" long.
(The Minie is a .50--the x was a typo.)
The button reads "Hollander * Boston *" on the front. There is lettering on the back that I can't quite make out but I think one of the words ends in "RTS". (Through some googling, I found that there was an LP Hollander who made at least women's clothes.)