The only unit I have seen one on is a departments ambulances and they love them for the reception. Does not seem any better than a whip. I was just curious as to who made them and prices. Those are it though.
I think what you are looking for is the Untenna. Its a dome style low-band (~45mhz) that is about 8" in diameter and 6" tall made in Long Island. Haven't seen it many places off of the island. PM me if you still want the details and dealer that carries them.