I would assume that the airbag wheel from another 92' E34 would probably fit, but i bet it would be a whole lot of work to wire up all the sensors and electronics to get the airbag to work if your car did not originally come with one. And as for looks, the early airbag wheels like mine are quite big and ugly.
Pic of early 90's US spec airbag wheel (i'm not sure if there is a different euro version)