These are all small signal input tubes with the same pin out.
Please tread careful with this next statement since it is your gear
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. The lower gain tube 12au7 should not cause any harm to the circuit since it is providing less current.
You may however, run into an issue if subbing a 12ax7 where a 12au7 is required.
The other nomenclature you list are just different branding of the same tube.
i have had success subbing a 12av7 or 12at7 in the same scenario.