I had so many issues with this on mine between the ballast, fuses, and the bulb. I eventually just grabbed an LED all in one, wired it to the cab, and $11 solved my issues.
I think that's slightly a different issue than mine, I have no problem getting fluorescent bulbs to work (you need a working ballast,
FG-1E starter, and any 15W T8 bulb you can get at Home Depot or whatever).
My question was about the light properties of the original bulb the NAC came with in Japan, because the type of light you put in there can affect how the marquee looks. Different types of light render colors differently and can have a dramatic effect on the look of your cab. We quantify that with figures like color temperature (that is, is the light more yellowish or more blueish, measured in Kelvin), amount of light (in Lumens), and color rendering index (a numeric CRI value). If you have these figures from the original bulb you can search for one that closely matches it to get your marquee looking as close to stock as possible, if you cared about that sort of thing. Any light you buy will have these numbers either printed on it's box or manual or in a datasheet somewhere.
Anyway, in case anyone else is searching for the answer to this, I've figured out that the NACs probably did originally come with Toshiba FL15D (the "D" is for "daylight"), which is 6500K, 760 Lumen, with a CRI of 74. It may have also come with a Toshiba FL15N which is 5000K, 820 Lumen, and CRI of 70. Personally I would use a 5000K bulb like the Philips "Natural" 15W T8 you can get at Home Depot because under dimmer lighting in your house 6500K would be very washed out looking.
EDIT: also in response to
@stj, yeah the lumen value is only good for the "initial" intensity of the light, but it still has value because it kind of determines how far it will drop. so with two different fluorescent bulbs with similar initial lumen values, you can have a (very) rough idea how they will look with age