Yes, they were an option on E3s except for the 3.0Li which had them as standard equipment from the factory. The bracket is also super rare which is why yours have the home made ones. It is a very difficult shape to replicate.
And the super duper rare BMW orange fog light covers. I had a set of these that went with my car when I sold it.
There is no E3 market value established for those since there is so little demand. Other period cars used them and they are nice, the mounting is almost always the problem. They have an unusual mounting attachment.
I don't know...Whatever someone is willing to pay for them