You need the entire palmrest assembly: [URL] Service manual has the details on how to replace (read carefully - - it's not a trivial procedure). [URL]    
Greetings! My wife accidentally spilled oil on her keyboard, and it ceased to work because of it. The problem is that despite being potentially able to clean underneath, we need to find a replacement keyboard. We are aware that it isn't a regular keyboard (the lack of replacement parts on the internet makes it evident), but we desperately need a solution for this issue. Can we get any help? Thanks in advance! David
Dell Inspiron 5491 2-in-1 keyboard replacement