@Caplion, These are all I could find after searching publisher's website, twitter and an auction website. My understanding is that these postcards came with limited paperback editions of the volumes. One postcard per volume. In other words, for volume 1, some copies shipped a postcard of Fury, while others, a postcard of Niña. For volume 2, the full bathhouse is actually 3 postcards. The censored version was the one with the highest quality I could find. Some uncensored postcards were sold at auctions.
And no, only postcards.