Supposedly posted to /r/darknetmarkets. I haven't seen any links to actual posts yet. I did do a quick search of the sub for comcast, and found nothing. I don't see why the darknetmarkets mods would delete it, and the only other explanation is that it's entirely made up.
Thanks. Guess it is there after all, and either reddit search is lame, or I'm lazy. Possibly both.
ETA: Just checked it again, noticed that the OP of that thread deleted his account. Could be he wanted anonymity, or could be that he made it all up. Hmm...