Can I replace my ethernet port?

Is the ethernet port is part of your board? If so, you will need to get the schematic of the board itself and if your are good with a soldering gun and know what you are doing, yes you can replace the port as it is soldered to the board itself.

Make a mistake, get a new board. Risky

Honestly, getting a seperate card would be the way to go if you're board is working fine outside of the Ethernet port. Especially if it's a high end board.

Your Ethernet port appears to be part of an I/O card assembly.

If you’re really good with tools, and understand what ESD is and how to avoid it, you may be able to handle this.

The service manual for your laptop is here. Before doing this, you might want to check out the following, just to be sure…

Have you checked to make sure the cable is good? A bad CAT-5 cable will cause lack of connectivity also. And unless you’ve done a LOT of plugging and unplugging of the cable, or dropped the laptop with it hanging by the cable, that port may not be your problem. When you plug a cable in, do you get any lights at all on the port? Are you sure the driver hasn’t been corrupted and needs to be re-installed? The connector on the motherboard (circled in the pic above) might also be the problem, and it’s really impossible to tell until you dig into it.

Good luck!