So here is the full list of tubes for the replacement of the 6j3's that can go into the amp. The preamp can take the 5654's and I do have a set coming.
6J1, 6ж1П, 6AK5, 6BC5, 403A/B, 5654, EF40, EF95, CV850, 6J2, 6ж2П, 6AS6, CV2522, EF11/732, CV4011, 6J3, 6ж3П, EF96, CV848, 6BC6, 6AG5, 6J4, 6ж4, 6136, 6BX6, 6AC7, EF94, 6AU6, 6J5, 6ж5П, EF80, CV2521, 6F36, 6AH6, 6AN5, 6K4, 6K5, 6K4П, 6BA6, 6DA6, EF89/93, 5749.
So I do still need to do more research on this to see if someone has any suggestions. My hope is to use something other than a second set of 5654's to bring out a bit more from the setup. Something that will help the preamp with bass and treble output and separation. If that possible.