It's a vapex 3300mAh 6V battery pack (bought new off ebay a few years ago).

I have actually found another 6v pack however I am not sure of it's condition. It hasn't been charged in a long while. I am going to cycle it a few times to guage it's condition and will let you know if it's in a decent condition.

I'd be happy to sell you both 6v packs (assuming that the second one is in a good condition) for a fiver each plus postage. PM if you are interested archie.