Nothing suggested King Cold had transformations or that he could suppress his power.
It's implied that suppressed Mecha Freeza ~ King Cold's full power. Gohan said suppressed Mecha Freeza was way, way weaker than 100% Freeza, but that level of power could be of help against Namek SSJ Goku. Based on this, you could have an accurately range to place King Cold. I have:
Freeza (100%) 140,000,000
Goku SSJ 150,000,000
King Cold 80,000,000
Mecha Freeza (suppressed) 80,000,000
~ Full power 160,000,000
I like having suppressed Mecha Freeza being at 50% of his full power.