I would be getting 6m of your main power cable (or two 6m lengths of 4AWG if you dont want 0AWG). 2-3m of 4AWG earth cables, and if you do go 0AWG then 2-3m of 4AWG power cables and the distribution block.
Depending on where you want to mount the crossovers, you'll need in between 10-20m of speaker cable.
(10m for front mounted crossovers, 20m for rear).