I have seen this type connector, but not in this size. We use them in the telepnone industry, most especially for station wiring to multi-line key sets, and other analog voice/signal applications. The most common variety is 25 pair (50 pin), but I have seen them up to 32 pair (64 pin). All are double row and come in male & female styles. The term used to describe them was always "cinch" but I think that referred to the original manufacturer. Also notice it has the same basic configuration as a standard "Centronics" printer interface (just not as many pins), so it could possibly a condensed version of a centronics printer interface cable. You may want to look online for telephone cable suppliers such as GreyBar Electric or Anixter for a match.
Dialtone