I had to order tires out of Canada to find something in stock, but this is what I ordered for mine. I went 10MM narrower front and back to find a winter tire.
265/40 R21
https://www.1010tires.com/Tires/Pire...zero+3/2679500
305/35 R21
https://www.1010tires.com/Tires/Pire...zero+3/2679400
The variance with the stock tires is less than 3%, which should be fine. I doubt the 10MM narrower will be noticeable.