I was able to buy the Hard Drive Bracket, SATA Cable, and Screws on ebay for $10. They were for the Inspiron 15 3511, but will work on the Inspiron 15 3525. Problem Solved. 
Where can I obtain the Hard Disk Drive Bracket, Cable, and mounting Screws to add a HDD to this model laptop?.
Adding a HHD to an Inspiron 15 3525