Hi,

Here’s a teardown video for your phone.

At 2:47 minutes into the video it shows the loudspeaker/headphone jack assembly (supplier example only) being removed from the phone.

There are other parts suppliers online that may suit you better. Just search for Galaxy Grand Duos loudspeaker/headphone jack to get results for suppliers.

Most of the repair guides on Ifixit are created by users, just like you! If you feel like creating a guide whilst repairing your phone, please feel free to do so. Here’s a link that will help you to do this. Others in the future will thank you. How to Create a Guide