Q3 and Q4 work as CCSs so you can keep them as J113 as I don't think putting 2SK170 in those positions would make much difference in sound. The value of R7 and R8 would not need to be changed if Q3 and Q4 are not changed.
If you wish to change Q3 and Q4, then choose resistor values for about 3mA and 9mA:
If you wish to change Q3 and Q4, then choose resistor values for about 3mA and 9mA:
