This is the thread on to the antenna body type of cable

The one I have is too corroded so the threaded nut comes off the end of the cable and won't draw the cable end into the antenna body

The cable can still fall out with the nut tightened

They were originally 15' 6" long but maybe A body would be very close in length?

I'm thinking about this one but I'd be surprised if the threads were compatible, it probably fits just repro antenna bodies

https://www.classicindustries.com/product/1965/chevrolet/impala/parts/b9041.html

Let me know what you got thanks