If you have your old one you can look on the specs on it and just order a generic.
I looked through my stuff and can't find it. I moved two years ago and things got put in boxes and my small box of electric components seems to have decided to play hide and seek with me.
If you have the battery holder with rechargeable AA's in it you could just get a Battery Charger for them or just use AA Alkaline or Lithium's in it.
I gave my big country to my nephew a couple years ago, so I cant remember if it had an eight or ten cell pack in it. My M-1 Bandits both have eight cell packs in them, I still have two of those and they work well plus I have a Minaska amp that I use with a portable CD player. Minaska made some really good stuff.