I'd be willing to bet your pot pie pot will be large enough. Even big ole brahmas have a lot of feathers. You'd be amazed as how much feathers increase the perceived size of a bird. Like a fluffy long haired cat. Know how they get all skinny when wet?
I don't have an outdoor heating element. I heat water on my stove, bring it to about 165*, filled almost to the top, and keep it on the lowest setting to maintain the temp. Then I go dispatch my bird and hose him off before I put the pot in my sink to contain the overflow I plan on, to make sure the water is deep enough. I heat my water slightly hotter than I really want it because when I drop a bird with cold water all over it, I'm sure the temp drops.
I see no reason why you couldn't heat the water on the stove and bring the pot outside. It should retain heat long enough if you leave it on low to keep it warm while you dispatch.
Oh, and remembered something else about the benefits of the pre-scald bath: it really must help with the water penetrating down to the skin during the scald. Think of a hard, dry sponge. Gotta get it wet first before it will soak anything up.
Oh! And don't boil your scald water! 150-160 will not cook the skin like boiling water will.
And I'm sure you've read this before, and it's very true: once you get enough feathers off, the bird will very suddenly stop looking like a dead animal, and will suddenly look like something for dinner.
There's a thread here with some photos of processed heritage type birds... Lemme see if I can dig it up.
