PP 1624's. this is a glass enveloped version of the 1619. Front end will be a cascode differential amp. One grid grounded so it will SE:PP phase split. One GZ34 rectifier, two 2.5V/2.5A Hammond filament TX's( or perhaps a 5vCT/2.5v-parallel connection with seperate 2.5v windings( PN TBD ). One L-C filter. The 10 Hy/300 mA Hammond is a likely suspect. Perhaps a custom Heyboer... OPTx will be a 10k a-a with g2 taps at 20 and 30%, perhaps 40% as well for future as yet undetermined application/experimentation.

CCS for the cathode of the input stage would be very similar to the Guinevere plate loads. Additional CCS for Ec2 ref would be LND150N3 based and similar construction.
regards,
Douglas