You used to be able to get Daylight Balanced screw-in fluorescent bulbs from Durotest < http://www.durotest.com/ >. They've always been a quirky company to deal with and I think they may have changed hands and shrunk their product line. Nevertheless, their initial claim to fame was the Vita-Lite, a broad spectrum daylight balanced fluorescent light and they had come out with several variations since then. It might be worth your time to have a conversation with someone at the company.