My Lexus replacement battery was 600CCA this is in Canada and p/n was C0PBS-8497R BTW that's a zero in part number. A little tid bit here, VIN's and part numbers within Toyota system never use the letter O always use a number 0 zero.
I've found the 600CCA is more than sufficient.

 

Thats a part only available in Canada. Only thing I can do is upgrade it to a bigger cca. But then they have my car and I cant do nothing.😫

 

The 12v battery only powers the electrics and never has to start the engine therefore you only need very little CCA. What matters to make the battery last longer is Ah. I think my original OEM battery was 60 Ah and the replacement was also 60 Ah but it keeps good charge compared to the one Lexus said was fine.