wilco000,
I remember that musical since I used to listen to it in a vinil disk wheh I was a child, it's GREAT!!!
I desperately tried to help you to find its libretto, but - no way
(( You're right, no trace of it in the web. I couldn't even find whether it had been ever published in a book!
BTW, it differs very much from any variant of the tale 'Ali-Baba and 40 thieves'. This is a piece written in 1981 by Veniamin Smekhov (Вениами Смехов), one of the greatest Soviet and Russian actors and a very witty person
. 2 years after that the same actors you can hear in the audio play made a TV film (I've never seen it, thou...)
The music is written by Сергей Никитин и Виктор Берковский, I have the idea that it's possible to find at least some lyrics of the songs of this musical as lyrics to their songs.
Hope this will be useful. And - enjoy the play, because it's worth it