If you look on the forums there is a bit of discussion about whether springs are "handed". The following information is from the manual....
Japanses Front - BOTH are 41111-82A30
Spanish Front - BOTH are 41111-82A20
But looking at the back..... For a right hand drive car..
Japanese Rear Left - 41111-81A30
Japanese Rear Right - 41111-81A50 ie. They ARE handed
For a left hand drive car:
Japanese Rear Left - 41111-81A40
Japanese Rear Right - 41111-81A40
They are NOT Handed Clearly they expect drivers in RHD vehicles to be fatter.