Is it possible to have a hysterectomy, rectocele/cystocele repair all under spinal anesthesia?

Yes. This operation is low enough down in the abdomen that it can be done with spinal anesthesia. You will probably receive some IV sedation to help you relax during the case. Discuss your requests for anesthesia with your anesthesiologist before the operation. Hope all goes well.
Usually. The repair will help correct the bladder and rectal prolapse. Vaginal narrowing can occur as a result of the surgical repair.