Top is 6SN7 CV181 6N8P 6H8C 5692 B65 ECC32. If want to try 6SN7 CV181 6N8P 6H8C 5692 B65 ECC32. Bottom is 6.3V ( ECC83 12AX7 ECC82 12AU7 7025 CV4003 CV4004 5751 ). Amplifier design use 6.3V ( ECC83 12AX7 ECC82 12AU7 7025 CV4003 CV4004 ).
eBay