A well pump seal section housing connects between a pump and a motor. Upper and lower retainers at upper and lower ends of the housing have outward facing cylindrical walls. A bladder has an interior in fluid communication with dielectric lubricant in the motor. Rigid upper and lower sleeves are bonded within upper and lower openings of the bladder. The sleeves slide over the cylindrical walls of the retainers and are sealed by seal rings. Fasteners secure the sleeves to the cylindrical walls.