I don't know how good this would actually be but I wanted to post it here to know how everyone thinks. I just thought that rare candies can be sold/bought at shop 200-300k each like Dusk Balls, Friend Balls, Love Balls etc. I don't know if this is any good it just crossed my mind.
Sounds like a cool suggestion, price may need to be adjusted as players who get them from donor kits may feel ripped off in a way but for maybe 500k+ could be a good price