Greetings to another "collector for life,"
I think you have a pickers check. What agricultural produce is grown nearby that needs seasonal workers to harvest? What are the names (initials) of farms and farmers that match "NM?" This Token would be given to seasonal workers who pick five units of produce to later redeem for cash on payday. If you dug it up it might have been recovered on the same farm where used and lost.
Good Lick with further provenance.