Great gift! It is a model 66 though I don't know which series. Mine is still one of my favorite machines. I love the way it sews. Buy either vintage bobbins for it or good ones from someone like Sew-Classic. The ones you find in places like Walmart and Joann's in the blister packs are narrow and don't fit the vintage bobbin winders correctly.
Have you either looked up the serial number at ISMACS or called Singer? That may help determine which series.
Rodney