If you decide to paint your wheels instead of powdercoating (which you should):
Is powdercoating bad for rims? Yes, and illegal in Germany. So is using heat to bend them back.
There is an nth amount of silvers to choose from, and there is no real right or wrong, but everyone needs somewhere to start in choosing a silver.
Our preferred silver in painting Basketweave type rims is is Mit.U25:
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If you want the factory silver for most early silver wheels use BMW paint code 144 (Felgensilber).
Thanks for posting all the great resources!