here. This disc is markedly lighter and more beige than the Black-on-Yellow disc. I considered that it might be faded, but if so, it managed to fade without fading the text or the color on the reverse side. As unlikely as that is, I also consider it unlikely that there are variants of such similar hue. Like the "Teal-on-Unbleached" disc, my current thinking is that this is a manufacturing blem. Cheap manufacture and poor quality control may have led to a wider variance in color than intended by design.
None of these late variants have confirmed dates yet. This one includes a mailer but without a post-mark.But the back of the envelope notes that postage is 10¢ for first class. According to this site the first class rate was 5¢ per oz from 1963 to 1967. A total of 10¢ would put the whole unit at under 2 oz. That's at least plausible. But since this mailer is missing it's cardboard inserts I can't be certain what the weight was. Until I find a complete unit no confident estimate can be made.
There is no text on the disc itself, but the mailer is labeled in messy cursive "Maybell Machine." The recording spins at 45 rpm and has an outer edge start. the recording levels are pretty low but what's going on is quite clear. We have a drunk teenager singing acapella. She sings what sounds like a hymn for about 45 seconds them busts out a couple bars of Jingle Bells before getting cut off.