I've gfot the single band model of that set it's a good player on batteries. The B battery current is about same as a transistor set @ 12ma. Filaments are 200ma. I used 4D cells in parallel and work out fine. Not sure how long they would last maybe 10-15hours. I get the cheap ones from the $store. The major plus is that since your not plugged into the ac line it doesn't pick a whole lot of interference. Bit like a humongous wooden portable.
When my pals were reading comic books
I was down in the basement in my dad's
workshop. Perusing his Sam's Photofoacts
Vol 1-50 admiring the old set and trying to
figure out what all those squiggly meant.
Circa 1966
Now I think I've got!