"Mail-Order Brides" sounds like something out of an F. Scott Fitzgerald novel - sepia-toned and quaint from a simpler time. Let's just call it what it is - human trafficking.

Maybe the Gorn ate the Tribbles off-camera.  He did look rather well-fed.

Nope, that wasn't Vulcan.  That was "The Guardian Planet" - there was a "Guardian of Forever" in the background (the big stone semicircle).  See the TOS episode "The City on the Edge of Forever" for more information.