Cracked Glass LCD is undamaged why can't I find the part?

Late 2011 MBP fell off my desk while in the closed position. It's working fine save for the cosmetic nuisance i.e. a spidercrack in the display glass that I've managed to keep together using a ZAGG iPad screen protector.

Only options here on site are for total LCD replacement nothing for the top glass only?

It's not as though the LCD is glued to the glass like the new Iphones and Imacs so just wondering why or where I could find such a part without the unnecessary LCD.

Thanks,

Michael C.