take out the old stuffed bat and tray ......
Measure the space you will have to fit a new battery in there......
go to either battery world or some thing like that......
and see if they have one to suit, or that comes close to fitting the area....
I did this for my zook and my statesman that I had, $350 for the one in the statesman, But it was a Huge battery that would keep my stereo running for 4 hours

. Zook battery was $135, twice the size of the standard battery....

and no leaks if it flips

I hate going to weddings because all the grandma's used to poke me in the ribs saying you're next, you're next. They've stopped doing it since I started doing it to them at funerals.