By chance, does anyone have a full or vocal score of Cherevichki/Les Caprices d'Oxane/The Slippers (originally '?????????'), 1885, opera in four acts by Pyotr Ilyich Tchaikovsky?
Even if I wanted to buy the score, I couldn't because it is not even on sale... LOL.
You should check with whoever owns Belwin-Mills/Kalmus now.
(I have their octavo-size reprint of vocal scores for Vakula the Smith and its revision, Cherevichki, at home. However, there are pencil marks all over them from when I was working with the libretto a long time ago, so I wouldn't be able to upload PDFs soon if at all, because of all the editing I'd have to do to remove them.)
Another option is that you could try interlibrary loan at your local library, or, if your with a university, with its library.
"A libretto, a libretto, my kingdom for a libretto!" -- Cesar Cui (letter to Stasov, Feb. 20, 1877)