You can still get unbranded TY discs from online vendors, although they can be a bit pricey. For branded media, I would lean toward any brand that packages Ritek discs (TDK, for example). CMC manufactured discs have never given me problems, but I think the general consensus around here is in favor of Ritek over CMC.
TDK uses CMC discs as well as Ritek, so be on the lookout. See
this thread to spot the differences between CMC and Ritek spindles. I would also recommend Verbatim DataLifePlus media. Make sure they are DataLifePlus and that will ensure Mitsubishi discs inside. By the way, to find which media works best with your burner, consult the
Media Compatibility Thread.