That was published by UME, which is part of Music Sales Group, so you should be able to buy it from Vanderbilt, or Musicroom.com, or Sheetmusicplus or one of those big dealers.
I did find the Moreno-Buendia through interlibrary loan. I was surprised to find it is not a difficult part. I finally got the Montsalvatge Variations at a great cost from Spain, to find the piece was not worth the trouble.
Meanwhile, I have been composing much music in the Spanish genre, which I hope to publish in the coming year.