Small diameter copper capillary tube may be impossible to obtain. Unfortunately, it's apparently not produced in the US where you can actually communicate with manufacturers. None of the f's in UK, China or India will answer an email, even when it's routed
through an intermediary like Global Sources.
This brings me to Plan B. Hypodermic needles. These will be much more difficult to work than copper. They're brittle stainless steel but what can you do? At least they're conductive and available in a variety of diameters. These particular needles are 0.87 mm OD. Slightly smaller than the smallest copper cap tube on the planet. It should be up to the task with a good hi-temp anti-corrosive conductive paste like the SS-30.
The coil is another one made out of 32 AWG and a little more carefully and tightly wrapped. Again, it's 3½" around a more orderly little bundle of grapho-glas wicking. It reads an adjusted 3.5 ohms with the needles and 3 mm of legs inserted into each pole. When powered up it starts going red within a second. The coil is actually heated bright red in this picture but it doesn't show up that way. Must be the flash.
I'm thinking it may be a challenge to "solder" this stainless steel tubing to the battery connector without completely melting down the 4-hole system. Anybody have any thoughts on this? Eh, never mind. That ain't gonna happen.