Garage Door Cable Thimble

One side of the garage door cable has this thimble(see the picture with a ruler) installed on the lower bracket. It seems the thimble was installed when the cable was crimped and I have to break it to remove from the cable. Not sure if this is done by the Overhead door company or the cable suppliers they have, but I can't find a replacement.

When the torsion spring broke, the cable was released from the garage door bottom bracket on the side without that thimble. Also the cable without it was curled up. The cable on the side with a Thimble was still stayed in place and it was still nice and straight after I took it apart. I only became aware of the missing thimble after the broken torsion spring, not sure if the Thimble fitted on only one side is by design or installation error or break apart(less likely) when the spring broke(can't find it).

Originally I think the thimble will prevent premature wear out on the lower brackets and the cables. Now I think about it ... maybe it's