Hi @cyppo ,
Here’s a link to the [http://h10032.www1.hp.com/ctg/Manual/c03922401|service manual] for your laptop, taken from this [https://support.hp.com/us-en/product/hp-envy-17-j000-notebook-pc-series/5354973/model/5390674/manuals|webpage]
Scroll to p.72 to view the necessary pre-requisite steps and then the procedure to remove the hinges and top cover (also known as the palmrest).
On p.21, item #2, you’ll find the part number(s) for the top cover.
Search online by typing the part number ''only'' (appropriate to your particular model variant), in the search box of your browser to get results for suppliers of the part