From the link below that me and my friends went to visit
Mr Toshiaki Kurashima of P&C Electronics.
And made power amplifier with his output transformer that use WE iron core.
I also bought his 618B rebuild transformer with WE permalloy core
that taken from high quality repeating coil like WE111C
to make MC step up transformer like people done with WE618B.
He was selecting all cloth wires with same color as original WE618B.
Date code just simple but easily peel off ... ;)
Neat metal can, easy for who want to spray into favorite color.
Assembly in an enclosure, copper braid shield cover on twisted wires too.
Complete with pinewood.
Separate inputs without any switches.
Just burn-in before A-B test with original WE618B soon.