Get him to take a picture of it and post here what he wants. I know nothing about what he actually needs but pretty much every website that showed that part number has a picture of black weatherstrip curled up in a circle, and I know that window weatherstrip is softer rubber that goes around most of the glass. Hard plastic or metal cant do that.
If he has a leak, window trim of any kind doesnt stop that. They are purely for cosmetics. If he has a leak thats a break down in the urethane bead that seals the glass, that would require removal of the glass. What does he want it for?