Model 121-F question

[hawthicket]

I have a model 121-F 22 rifle that has been in the family for 50 some years. It is unusual in that there are a significant amount of engraving on the gun --as if it was custom made. My grandfather's initials are imbedded in an gold oval at the bottom of the stock. THs gun is in perfect condition. Can anyone tell me if this gun with the engraving was a standard offering by Remington or if the gun was augmented by a 3rd party with the engraving. I have seen similar Model 121-F guns on the internet ( similar engravings), which leads me to believe this was an offering from Remington factory. See pictures

Thanks

Jeff