That amp expects the Cobra pickup. It is not a common pickup that produces a small signal voltage.
The first stage is indeed an oscillator at some high freq I forget. The pickup has an inductor in the tuned circuit. The moving needle detunes the oscillator as it moves. SO the input stage is almost like FM radio. L1 is part of the tuned circuit. I have a CObra tonearm for the shop, so I can plug it into the amps. I inject audio into the second stage for testing. To test the first stage, I plugged my CObra into it, and dragged my finger across the needle. If that came through the amp, the stage was OK.
Your cap values are so small because they are in a circuit operating at way high freq, not audio.
When stereo came along, CObras went away as they could not make stereo.