I've done several battery radios, and the most difficult ones I've done were a couple of Zenith farm radios, a 5F134 and a 6V27. Leaned plenty from that pair! Had to build some fairly elaborate power supplies for those ones. I'll admit the 5F134 power supply was a bit of overkill (I used a 135V TV voltage regulator and a big transformer), and the 6V27 I'm still working on, with the intention of building a solid state vibrator replacement and run it off of a 6V power supply. A bit ambitious, you think?
Armed with the info I learned from the Zeniths, I've had a better time with the smaller farm radios I've done since, 2 Coronados and 2 Philcos, the latter being a 42-122 (covered in the "Latest Philco Save" thread), and a 40-95. Both are pretty simple circuits and not difficult to power.
I've got an AC supply I built that puts out 1.5V and 90V, but I've also built some battery packs that work great. A trip to Radio Shack will yield everything you need. A project box that will hold 10 9V batteries, battery clips wired in series, and a couple of D cell holders wired in parallel. I also use the 4 pin power connectors they sell for easy exchanging of the battery pack or the power supply.
If you like, at some point I can provide the schematic for the power supply if the group is interesed.
Bill