Ok, update to an old(ish) thread.
This dye, Erythrosine B (CAS: 54530) or Acid Red 51, is available here on eBay for chump change. This dye is in the Kodak list above.
I'm really interested in finding cheap sensitizing dyes for spectral sensitizing, and not necessarily because I am going to try to make a color-sensitive film tomorrow, but to put the possibilities forth so that anyone making emulsions might be inclined to experiment with this stuff down the road.
Sure they might not be the best or most efficient, but they will work, no?
Also, to make panchromatic dichromated gelatin for holograms they use methylene blue as a red sensitizer and Rhodamine G6 for blue/green. Do these dyes have any effect on silver-halides?