I'm not saying it's a bad idea, I have a red bulb too. It's "handmade" by removing thick red rubber from a "golf ball" decorative 7W CFL and stretching it over a similarly-sized 6W 2700K LED that has instant start and higher light output (not to mention, the taut rubber won't send glass ball shards into a mercury-vapor-filled tube if it happens to fall). It is not as monochromatic as pure red LEDs, I think it's close to what the phosphor-based red ones emit (with a lower efficiency of course since I discard the blue and green while they turn almost all blue into red and no green) and those are marketed as cicardian too. I have to avoid looking straight into it though: the pupil is wide open because rods don't react strongly to red light so long-wavelength (red) cones get massively overloaded and I see a green spot for a while.