This is a very new model - it's the same as an Inspiron 5370, so if you can find a cover for that it'll work fine.
It may be Dell is the only place you'll find the part for what's a current model -- the parts vendors are unlikely to have used parts for sale on a model this new.
I called, and gave the service tag and express service code for the laptop. They were not able to find the laptop in the system. They said that the service tag and express code did not show up at all. I do not know why that would happen.
The part number that I was able to get was [210-ANPC]/8C32H for the bottom cover. Since it is so new, I was not able to find any online. They will also not let me know the price, since for whatever reason, the service tag is not in the system. Is there any way that you can help in that respect?