Unfortunately replacement rectangular Hoppers are no longer available. To elongate the life of your rectangular Hopper, Disks can be removed without removing the Hopper by unhooking the Pull Back Spring, lifting up on the Hopper, and the Disk will slide out the front of the measure. Leakage can be minimized by reducing the amount of clearance between the Disk and the bottom of the Hopper. To do this, carefully file the tops of the Risers that the Hopper rests on when attached.
However, if a replacement is necessary, you can upgrade your Auto Disk to the Pro Auto Disk. The Pro Auto Disk Hopper has an soft plastic Wiper built in to the base so it is operated at zero clearance. The parts needed to upgrade are listed below for you:
AP1646 Hopper
AD3396 Wiper
AD1509 On/Off Valve assembly
AD3398 Screw for On/Off valve
FA3407 2 required Screws for valve assembly
AD3285 Pull back lever T
AO1688 Bead chain
AD2749 Spring for bead chain
AD3397 2 required Brass knurled thumb nuts
AD1210 Swivel Actuator
AD1449 Actuator lock
AD3405 Knurled Adapter bolt
AD2949 O-ring for drop tube
90792 Adjustable Charge Bar(optional)
AD3398 Pro Auto Disk instructions