First of all thanks everyone for your insights, it's very helpful. I ordered original Toyota lower ball joints and upper ones too. I also noticed my cruiser isn't equipped with dust covers (43346-60011) for LBJ, maybe I should order that too. They're rather expensive at 40€ for each one.
About the front coil springs: what's the original and stock length for them for my KDJ95 (year 2002)? According to schemes found on Amayama and such they vary from 352mm to 390mm-ish or even more. I found some KYB ones with 365mm of length and have a feeling that's the stock length for coil springs but am not sure. I'm guessing my coil springs are original but I can't really measure them when they're installed in...