Where would I find these?
First, try using the Start button (I don't remember if it's was mandatory on this model- their semi-automatic tables only needed for the tonearm to be moved from the tonearm rest to make the motor start).
If this works, we're done. If not, raise the tonearm with the cuing lever and move the arm toward the album- if the motor starts (and I think it will), returning the levers to their home position should make the audio work.
If that doesn't work, the worst choice would be to clean & lube the cam and return it to original operation. This would cause the muting circuit to work the way it was designed- to eliminate a thump when the tonearm lifts off from the album. I called it "worst" because it can affect the sonic performance, but it would still be better than most automatic turntables.
http://dual.pytalhost.eu/626s/626s-16.jpg
Next, would be to disable the muting circuit. If you can solder, you can do this. In the link below, you'll see two photos- the bottom one shows the circuit board with the muting circuit near the lower right (it has one corner as an angle and has a metal shield over it. At the bottom center, it shows the audio cables coming up and bending, to go to this board.