DanG wrote:
It is called a Bowdan cable. Some are stiff enough to function in
both push and pull like a lawn mower throttle, some tend to work
one way with spring pressure moving the other like a bicycle
brake. If it needs to stay in the sheath, you will be better off
replacing.

I'd agree. If the old part is no longer available, perhaps the end
fitting could be taken from the old one and attached to a new cable.
W/O some idea what the end/function might be it's hard to say anything
more, but a mid-cable splice is unlikely to work well. Unless there's
a return spring in the compression mode of travel, the spliced section
will tend to buckle if there's any force of significance at all
required.