I have a bunch of random blanks, including some of the black CDs. These were from PNY Technologies - Black Diamond CD-R. I also have some assorted colors of Memorex CDR media. If you want to experiment, let me know and I will send you some to test. I also just found an entire sleeve (100) of unbranded CDR media that is not quite as dark as the original cyanine, but certainly not any of the modern clear (or near clear) dyes...