How much is it to replace a usb c port on a macbook pro?

We can't honestly tell you how much it will cost to get this done. This is a user forum site and it is all users like yourself that come on here and help to assist others when their computers are giving them issues and attempting to give them some advice on what to try. I would suggest taking the computer to an Apple Store Genius Bar and have them take a look at it. They aren't going to charge you anything to look at it, and they will be able to tell you how much it is going to cost to get it replaced before you turn it in

Depends on which model. On some, the two on each side are on a daughter card. On others, the entire mainboard must be replaced.

We don't have 'which model requires which' information at hand here. If you have an Apple-owned store available to you, your appointment for an evaluation, including an advanced hardware test, is free.

Take it in to get an estimate of your repair cost for your exact model.

In or out of warranty you can get a free over the counter 'Apple Service Diagnostics' test

Apple Authorized Service Provider Program - Official Apple Support

https://www.apple.com/retail/geniusbar/

https://checkcoverage.apple.com/

https://support.apple.com/my-support