You don't need to use A5, for example A1 is as good as A5.
Those LDR's can have different values, that's how it is.
You can add a potentionmeter to the resistor, or add a resistor to the 10k to increase the value of the 10k until both LDR create matching analog values.
Increasing the value of the 10k resistor is quick and easy.
It is also possible to solve it in the sketch in software.
Since it is a log scale, you need perhaps to do log calculation to get a good match.
Or use the multimap function.
http://playground.arduino.cc/Main/MultiMap
You could create a table from 0 to 1023 and a table from 0 to 100%.
If you do that for both, they should match.
The 0 to 100% doesn't have to be very linear or very specific. You can define yourself what you would consider to be 0%, 50% and 100%. You can add more data points for more precision.