Preludes that go with Fauré's Requiem?
In two months, I will be performing excerpts from Fauré's Requiem in a school-related concert. However, the conductor has decided to skip the first two movements and the Agnus Dei due to limitations with the choir, so we will begin at the Sanctus.
I find it a little unsatisfying to skip the first movement, so I would like to ask the conductor if I can play a short prelude in lieu of the first movement. Before I ask, however, I would like to have some idea of which prelude I might play. My main considerations are that the prelude ought to match the mood of the Requiem's first movement, and that the key of the prelude should be related to Eb major so there isn't an unpleasant gear change when the Sanctus starts.
Does anybody have any recommendations of pieces I could use as a short prelude with these criteria in mind?