Mercer Parts Inventory Tag? Original?

From the trove of parts I received with my Raceabout, here is an inventory tag (I think) attached to an Eisemann Magneto. Allowing for nearly 100 years of 'shopworn' patina, I think there is a chance it is NOS. Many if not all of these parts surely came directly from Vince Galloni from whom Sam V bought the car. Since Vince got many of his parts from the closed factory, it seems possible this could be OEM. Anyhow I thought it was pretty cool and should share.