Π/3 radians phase circuit.

Hello.
I need to design a Π/3 radians phase circuit, to calibrate my CS5463 internal phaes (i'll calibrate it so it will read Π/3 phase when i enter it Π/3 phase).
I already calculated the needed capacitor and resistor:


I have a few questions please:
1. How can i avoid entering capacitive/inductive factors to the measurement?
will using the AC mains voltgae add capacitance/inductance to the measurement, comparing to using a simple signal generator?

2.
Where can i find a 60ohm resistor, 250W?
I dont have a budget to buy one, and i need to know exactly its resistace because i need to know what phase the circuit has.
Also this resistor must have no capacitance or inductance.
What would be a good replacement?

Thanks.