Motorised input rotary selectors ALPS ASD1017 / Yamaha VT148400 were used in several Pioneer, Onkyo, Yamaha vinatage amplifiers. There were plastic gears that cracked during the time..
rotary selector 
cracked gears
Replacement gears were created using a precise 3D printer and tested for correct operation.
replacement gear (top) 
replacement gear (bottom) 
replaced gear in the assembly
Compatible devices: Pioneer A-501R, A-502R, A-701R, A-702R, Onkyo A 8051, 8940, 9510, 9511, 9711, 9911, Yamaha AX-1070 and more.
The part is also labeled Yamaha Rotary Switch SRBA Gold VT148400 in Yamaha devices.
Compatible with ALPS ASD1016 Input Selector.
Compatible also with Sansui AU-X517R amplifier.
Available in e-shop.
Dear Mr. Schiller,
I’ve got last year the gears for Alps motorized input selector from you. Now I finished the repair of my Pioneer A-602R. I replaced booth gears and it’s work fantastic. Many thanks for that👍