Your best option for a sun shade for a Deuter Kid Comfort 1 Child Carrier would be the Deuter Kid Comfort Sun Roof. Be aware that sun roof is compatible with model year 2019 or newer child carriers. Additionally, the Deuter Kid Comfort Deluxe Rain Cover will fit over the sun shade and help keep your kiddo dry on rainy days.
Hope this helps!
At REI, we believe a life outdoors is a life well-lived.