Found it. It's the Latin set from the MN series that's preinstalled on Mac computers for foreign character sets. Malayalam MN, Tamil MN, Gurmukhi MN, Kannada MN, Khmer MN, Lao MN, Myanmar MN, Oriya MN, Sinhala MN, Telugu MN, etc.
Edit: I don't think there's a legitimate source for Windows, but...