nzprius2001

recently 3 warning lights came on in my 2001 Prius; red car exclamation mark, triangle exclamation mark and engine in red and had no reverse gear. Car was towed to dealer and following error codes came up: P3000 - battery control system, P3006 - battery levels unusually different, P3022 - battery block 12 becomes weak; P3030 - battery voltage defective live snapped, C1521 - motor and C1522 - motor.
I live in a small town in NZ and there's not much experience or expertise in fixing Prius here. The dealer has emailed to another city for info, so I am posting here in hopes that someone might be able to help me out.
Key question - is it worth fixing? - mileage is 147000 kms, so battery is probably due for replacement. I have seen quotes here of $3000 plus, that would be US$ I guess. NZ cost much more.
If I replace the battery what can I expect in terms of life expectancy and ongoing performance. Is it worth it with a 2001 model. Any light you can shed would be much appreciated.