The E80CC tube can substitute a E82CC tuhe if the plate voltage is less than 250v. So you can put also an ECC802s insted your E80CC in the left side (output board) of the chassis cirquid. It is completely the same design as my from Opus 120. Only the companies of the caps are not the same. I can replace mine also. Tue knobs and butzoms are 100% at the same position and the layout of the cirquit boards are the same. May you can ad all print names of tte boards.
I am 100% sure the tubes in your ps output and input stage are in the same design as the one from Brakemeier.
Is it not strange if even the knobs for MC and MM load and input selection buttom and cirquit layout design is 100% the same? I measured the difference of middle from the buttoms to the knobs. The buttoms are ca. 12mm lower.
From one knop to tze middle of the next knob it is 70.5mm.
So if this is also at your yours I would say......