The iPod Nano 7 carries a Multi-Touch display of 2.5″. The replacement part is specific to that panel, which is why the price you see is for this exact model and not an average.
A iPod Nano 7 Screen Replacement starts at $135.99 at verified shops in Miami, FL. The final price depends on your exact model — you see it before you commit.
Yes — every shop is verified and you see its warranty terms before booking.