As mentioned in my earlier post, I called Bestop myself, yesterday and spoke with a woman who researched my part request. It took her awhile, but she did find part # 332.01 still in stock and quoted the price at $6.95. (I doubt she could have known the price if the part was out of stock.) My guess is that when you reached out to Bestop, the person with whom you spoke didn't do a thorough research. You should call them AGAIN and inform them that a rep. indicated the part was still in stock, as of Friday 5/18.
On closer inspection of the 2 parts... you are correct. The driver's side bracket cannot simply be flipped. There is a cylindrical housing on ea. bracket that fits & holds the "horizontal bar" which is part of the overall framing. That housing would have to be cut and remounted to adapt a driver's side bracket to work on the passenger side. My sense is that a decent metal shop could accomplish this relatively easily.
So, IMHO, your best shot at accomplishing this task is again calling Bestop and ordering 2 ea. part # 332.01. By doing so, you'll, for sure, have one of them, and at least a proto-type that a good machinist can use to adapt, or make from scratch. My sense is that trying to find these 2 parts as a stand alone request on line will be next to impossible. And, even if that doesn't succeed, you are only out a total of $15.00., hardly a huge investment while trying to restore a classic Sunrider.