OP, ... call ARC. I would not be surprised to learn that a 10% variation is not critical.
I own an ARC Ref 150 SE amp. There is one bias pot for each matched pair of 2 KT-150 tubes. The set tube bias is set at 65 mV and the slave can be between 57 and 73 mV. So, +/- 8 mV is spec. As a practical matter, I try to match my tubes within 2 or 3 mV.
I have no idea what the spec is for the V35.
BIF