I would say that with the plain background this one could very well be older than the one in the reply above. I would imagine 19th c. is not a bad guess. Trouble is, that backmark doesn't give us very much information. These buttons are not listed in CW books, and there was a large number of civilian brass bands, etc. for dances and social events in the mid to late 19th c.
Regards,
Buckles