When I needed one for my 62, I used 2 of the adapters for a Lokar throttle cable. I used one on each end. Although you may need to open the hole on the carb and also the trans for the stud to go through.
http://www.summitracing.com/parts/lok-s-1034/overview/
I went to my local hardware store and bought a length of small cable. I was lucky, in that the tube was still in the car, just not the cable. I suppose if you don't have the tube, a piece of brake line would work.