and have no fears about switching out the battery on my own.
Oh, you should be very afraid. The battery is glued in place and its removal requires flammable, toxic solvents that I would not store in my worse enemy's garage. Your computer should be new enough for Apple to service see: Obtaining service for your Apple product after an expired warranty - Apple Support) --at least check with them. I do not see the 2017 model in that vintage/obsolete list so they should service yours.
You can do a ship-in service with a notebook computer.
If Apple does it, cost is US$200 parts/labor. If a third-party shop, even an Apple Authorized Service Provider, does it, they cannot legally use the needed solvents in a retail environment due to workplace HAZMAT and fire safety regulations and, instead, have to replace the entire upper deck. That is over US$500 parts/labor.
If you ship it to Apple it goes to a specialized Apple refurb facility for service. Cheaper and an order of magnitude better. And warrantied. It you pack it to an Apple Store, they are going to send it to the refurb facility anyway and that will delay the repair turnaround by several days..
There area NO Apple-branded replacement batteries sold as a consumer part. Apple stopped selling notebook batteries as a service part with the Retina models. Any claiming to be "factory original" parts are scams. There are hordes of counterfeit batteries and other repair parts offered as original Apple on auction sites and other places. Apple warns against the problem on their Support home page:
At best these fakes do not work; at worst, they can destroy your computer. Dont't go there!