are the red voltages values corrected on the schematics ?
You're 5.3vac on the filament seems high a little, maybe add an resistor to drop the voltage a little bit, and see what the results it give .. your tp13 and tp14 are wrong -26v is not good ...
Are the capacitors good, not swollen, leaking etc .... check if you have some ac voltage on top of the dc voltages, maybe change all the capacitors in the psu would be a good start ??