Sorry, still not clear to me
"New" as in brand new - recent model 118 Featherweight II?
Or new to her - an older machine - like a 221?
If it's a plastic piece, I'm going to assume (?) that it's the newer model.
Did you search for a Singer dealer near you - maybe in a Sears store? If not, a sewing machine repair shop should be able to get the part for you.