They have 416C woofers (16 ohm) and 902/908 HF drivers. You can get replacement HF diaphragms through Great Plains Audio in OK.
Don't know the exact age of the speakers. They are after Altec switched to ferrite drivers. So post 1970's or after.
Someone will have better info than me. I am not too familar with the A8. I do like the 32b/c horns they have.
Are you planning on buying to restore them, or put the drivers in some different cabinets?
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