My idea was to go there at another time and look, if somebody else bought the one I didn´t want. But of course it might take long until I have all the ones I want. Ok, I didn´t read all the posts, we´ll have to wait what LL says anyway.
I just bought some gacha and came across this vendor which should be ok regarding the rule that you need to know what you are paying for.
And I like it much better than the usual ones because I know I won´t buy a double next.