Personally, I'd stick withe the OEM brackets.
They'll fit,,they are stout, they look right, and you don't need to worry about making
Adaptor plates or drilling new holes and using rivnuts or the like....
They can be found..
I had after-market mirrors on my truck when I got it - replaced them with the genuine ones as they didn't look right, and didn't have the "fold back" feature and had all sorts of excess brackets to stop them from vibrating creating lots of holes in the truck door.
I bought a genuine set of arms, and then modified them to fit them closer to the body - the arms are pretty substantial wall thickness - 4-5mm IIRC.
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