OzStock - 8 High Capacity Ni-MH Rechargeable Batteries $9.98 + Buckscoop Cashback
* 1 Pack of 4x AAA 1250mAh
* 1 Pack of 4x AA 3000mAh
They can be recharged up to 1100 times, which should hopefully last a while.
Even with shipping costs being $5.90, it's still a good price for 8 batteries.