Hohner symphonic 30n powersupply 1 PUBLIC

Hello, I am a noobie here and my knowledge of electronics is limited, but that doesn't stop me from learning. This is a great place to do that.
This is the power supply from an old electronic organ from the 1960's. I am replacing the power caps and thinking about replacing the old selenium rectifiers with new 1N4007 silicium diodes. On the original schematic there is only one transformer with dual output, here I have represented that with two transformers. The only thing missing from this schematic is the 300v voltage regulator which is done with 2 OA2 vacuum tubes (150v each in series) which I could not figure out how to do here. Output1 is +300v. Output 2 is -12v. Output 3 is -28v. The 300v are used for the oscillators (Wien bridge?) and the frequency division circuits (small neon lamps). The -28 volts is not very smooth but maybe that is because it needs a wobbly voltage for the vibrato circuitry? Note the use of a reversed rectifying bridge for negative voltages. Any tips or comments are welcome
Thanks

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