I wonder if MagnaQuest or Heyboer could provide good audio coils in those values. The cores they use in their audio transformers are much better than ferrite.I'll open up the tube crossover schematic in OrCad, size it larger, screen print and E-Mail it to you. You might also want to download the OrCad (PSpice) demo distribution and the 6DJ8 crossover model because those are the source files.