N.H C.Co. on your ID tag may mean North Hampton, Clark County, Ohio.
There are four towns in Ohio that would use the initials N.H. These are; New Hampshire,
New Haven, New Holland & North Hampton. If you keyword "Spence, one of the town names &
Ohio", the only town that came up with anything that mentioned the name Spence was
North Hampton in Clark County, Ohio. Spence appears to be an old name in North Hampton.
There's even a Spence Road in North Hampton.
Deeper search adding keywords like Civil War, Spanish American War, National Guard,
militia, etc. didn't bring up anything.
A quick search through the Clark County Historical Society online archives reveals nothing on an M. Spence, including on their veterans list. You could email them a picture of your ID tag.
http://www.heritagecenter.us/
Perhaps its a patriotic ID tag with no military association.
I agree with DCMatt's observation that it may be a catalogue item & late 19th century.
The above could be relevant or be a total blind alley.