Missing USB cover/cap

I just purchased a '15 Prius v Four to replace my '06 Prius II. (The transmission went out at 252k miles). The v is missing the USB cover and the rear cargo net. I'm wondering if it's a good idea to replace the cover or is it okay to leave the port open 24/7? If I replace the cover, should I be looking for just the cap or do I need to replace the entire unit/port or whatever specialty name it's called? Does anyone have a Part #? Any advice, suggestions and help would be most appreciated!

So far, it's a huge learning curve from my basic Gen II to this Gen III. I have A LOT to learn with all the gadgets and technological advances it has. It's, for sure, smarter than me.

Sorry if I posted this in the wrong section. I wasn't sure if I should post here or in the "Care, Maintenance, Troubleshooting" forum.

Thanks again for your help!