To answer the last part of your question I would say unlikely unless it is the one the OEM receivers were designed for.
In my experience with GM vehicles the shape was not only for function but also of design. These antennas were required for AM, FM, GPS, OnStar, SiriusXM and frequently had combiners and splitters hidden in the vehicle. I posted these pictures on the old GG but you will see a shark-fin antenna and one that used a small whip (removed). These are a far cry from the old telescopic antenna for your AM radio.