Achimba

I purchased a used Sony MZ-R55 MiniDisc Recorder. It did not include the battery bubblepack (for using AA batteries). I need one. Do you have one for sale? I have been using the MZ-R55 for live recordings. I have been able to use the AC adapter previously but there is an event coming up that I need to enter stealth mode and I will not be able to plug in. The gumpack batteries I have seem to suck badly. [i have read the comments about charging / recharging them in other threads on this forum.] I would like to use good old AA batteries, rechargable or otherwise, to power my recorder. Where can I get one?