There are ‘Laptop LCD Monitor Sites’ which may have the exact screen you need, but i would start by searching like this:
Dell Inspiron 15R (N5110) Replacement LCD - find the exact model designation. and note the ‘Connector type’ [there’s only a few types]
Then search for that Specific screen - Ebay will usually pop up first. Scrutinize what you are offered however, and you should find one for around $100 bones