Unfortunately for your model, there is no “non-touch-screen” version of your display. Also, It does not look like the digitizer is sold separately from the display assembly, so you will have to replace the whole display assembly. I found a fairly affordable display assembly though, and the replacement should be as simple as plugging the LCD in and screwing the hinges in place. You can find the part on eBay here: https://www.ebay.com/itm/Acer-Chromebook-C720P-Black-Lcd-Touch-Screen-Digitizer-Module-11-6/202344430135?epid=19020511573&hash=item2f1caafa37:g:k6wAAOSwm4NbJ5ud:sc:USPSFirstClass!89509!US!-1&frcectupt=true