Current Transformers CT's

I have A GE I-70-S Meter Form 3S TA 2.5 Kh .6 V 240 Just measuring KWh no demand

How do I select a CT to work with this meter For use on single phase 240v 200a service. Will use 1 ct and loop one of the primary lines.

And also how do you calculate the multiplier

What Brand And Part numbers Do you sugest using