Unison for movements 1,2 and 4 – the 3rd is marked solo and changes from harpes to harpe. Much more fun to have a companion – especially if there are other pieces to play in and not turning up just for those 3 movements.
Saul and Sylvia, I said “yep, that is the version I have” to the link that Sylvia posted. If anyone clicked on the imslp link above, it is very obvious the Pelleas referred to in this thread is the one by Faure. Tacye posted the next comment which referred to the Faure Pelleas by noting it is in 4 movements, 3 of which can be played in unison by more than one harp. She got it.
And speaking of death wishes, should anyone ever risk an encounter with the Schoenberg P&M parts my considered advice is to ensure you are several miles away!