They used to sell the case, and each airpod separately (with the total for all three being the same as a new pair), but it looks like they stopped? It was very useful when I ran over my airpods case with my LandCruiser, and it got a bit wonky (but was amazingly still fully functional).
And I wish I could just trade the Type-C case with my lightning case (with at most a tiny refurbishing fee), there are a lot of people who just bought the Airpods pro 2 last or this year and not likely to purchase again in 2 yrs