original focus diode specs
ECG503(NTE503)/RCA # SK3068
PRV: 14,400 Volts (No Load)
Forward Current IF: 0.5mA
Forward Voltage Drop VF: 260V @ 2.5.mA
i have 10 of these
Rectifier 2CL77
https://digchip.com/datasheets/parts.../2CL77-pdf.php
it SHOULD work IMOH,