For a few procedures in some of our optics labs and demonstrations we
use an old Cenco high-intensity light source based on a GE type CPG
projector bulb (6V, 18A, with a helical filament). The bulb recently
failed. (The filament looks OK and the resistance seems low enough, but
it won't light.) I had a replacement bulb (probably about 40 years old)
but when I went to look for a new spare, none of the bulb suppliers I
checked seems to list this type. I am wondering if anyone else has
found a suitable replacement bulb for one of these.