Selling for $2: https://store.acousticsounds.com/d/16517/Maurice_Abravanel-Berlioz_Requiem-HDAD_2496_24192. The recording is selectively discrete - the score calls for offstage brass bands in one section and the quad mix envelops you when they're playing - otherwise the mix is ambient (to my mind this is the ideal for classical). There's also a few others on sale, in 2 or 3 channels: https://store.acousticsounds.com/index.cfm?get=results&genreid=10&CategoryID=6