This is the first time I have ever heard of this problem. I have seen RVers who have left their antennas in the up position and had them torn off going under a low bridge.
The answer to your first question is no, you cannot buy a replacement wing for your antenna, you have to buy a whole new Control Head for your antenna. I am not even aware of any after-market replacement wings for Winegard RV Antennas
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