Sadly, Apple only sells the full uppercase as a replacement part which is quite expensive! If you look on eBay you'll often find subassembly parts like the keyboard alone. Here's a snap on what I found: eBay 13" MacBook Pro retina A1502 keyboards. As far as I know Apple is still using the same keyboard in the newest model so you should be fine. Make a good inspection on the connector and the location of the ribbon cable it should be the same as yours if not return it.
Now for the fun! Apple glued the battery assembly into the upper case so it's a bear to remove without damaging it.
Before starting things here it is strongly recommended to discharge the battery (run the system down). If you have the battery charged it could ignite if you pierce the battery case!
Also wear safety glasses and a face mask in a well ventilated area (outside in a garage), as the fumes from the battery are not healthy to breathe.
While some techs have mastered the technique needed to remove the battery it does take some skill and I'm sure they have messed up a few perfecting it (I killed two). So you may end up needing a new battery if you mess up.
The trick is to use Ethanol alcohol to soften the glue basically keeping the glued surface wet for a good 8 or so minutes (not flooded). Then using a fishing line drag it under the battery carefully pulling it across acting as a knife as you go add more alcohol so the glue stays soft and wet were you've pulled across already. As soon as you get to the other side carefully lift the battery and make a good inspection for any cuts or pulls in the plastic either could be signs of damage. I would not chance putting the battery back as it could fail not only damaging your laptop but set things afire!
So, given the amount of work and the risks you may want to just buck up and buy the full upper case assembly. Here's the part info: MacBook Pro 13" Retina (Early 2015) Upper Case Assembly - Apple Part #: 661-02361. You might find a used one for less.
In any case here is the IFIXIT guide you'll need to follow to gain access to the keyboard or to replace the full assembly: MacBook Pro 13" Retina Display Early 2015 Upper Case Replacement.