Thanks heaps for the info Steevsee 

Ok, so I've tested the D5 diode, it was working but I replaced it anyway and tested for 68 volts and got 140 volts 
At the CN5 68 volt pin, its reading 25 volts

R11 - 330k tested to 356k, so that was replaced.
Also R8 & R12 tested ok.

I've replaced: D6 - 1n5228, D9 - 1n4760, TR1 - MPSA92 and TR3 - MJE340

Im waited for caps to arrive for C10 & C11

68 volt test was done after parts were replaced.

Could it be the C10 cap ?