There is a split bench seat for Lancers. All '62 "A" body 2 drs except Lancer GT and Valiant Signet had a split bench. I'm not sure if there is any weight savings.
I believe the seat back was "split" on those for ingress / egress to the rear seat similar to a '69 Swinger Bench seat.
But not split in the Seat area - one solid bench.
@ slantsix - agree on comments on older style split bench. More modern cars with a split bench are fully split. To me they are just wide buckets that touch.
@ Dart66GT - any "A" body split bench seat from '61 to '66 will fit. Having the '62 specific seat tracks makes it a simple bolt in job. Modifications to use '63-'66 tracks are minor.