The throw isn't very long, when it is clamped to the shutter lever it is almost touching the shutter. But it does take a fair amount of force to push the lever out and release the shutter. The inner coiled tube is not broken, just the outer cloth covering, so if I can find a way to connect the torn cloth ends it should still have enough throw. I'll try the splint and tape first. Heat shrink tape would need to be large enough to go over one end, so probably too big.
I wonder if I can find someone to just make the clamp, and then screw a standard cable into it.