So it’s a 6 roller handrail drive assembly, then there should be 3 idler brackets with idler rollers, in between the HRD assembly rollers for belt tension. Also a handrail drive pulley (84 teeth, the big one), that has a metal ring around the edges of it so it keeps the belt from coming off, a broken belts switch arm that rides on the belt, and there’s one more stationary roller that is bolted on a plate inside the unit, and there’s a jack bolt on that for alignment, I would check all the rollers to make sure the bearings are good, it’s been years since I worked on one