Are you talking about a dataplate that is on the right hand side clamp bracket? Or maybe the cowling graphic that says "Yamaha". I am not familiar with the term "nameplate" with respect to a Yamaha outboard motor.
Can you provide a link to a Yamaha parts catalog that depicts the part in question? If NLA from Yamaha you can have a sign shop make up something similar.
No not the data plate, the name plate on the side of the cowl, it is not a decal or I would have made one myself. It is an actual name plate - just like on a car. it is mounted to the starboard side of the cowl.