You can find the RC090 style 5's quite frequently in the boneyard. Pick and Pull takes the wheels off most of the cars before they put them out, as they recycle them. I put in a Row52 search for 1995-2005 5-series BMW's, and when I get a notification I run the VIN through bmwvin.com. It will tell you if the car had the optional wheels by listing "S291A BMW LA wheel, cross spoke, 2-section" in the options section. I know the manager out here, and I contact him and buy them. You also find them in the trunk occasionally. A wheel with an unusable tire runs about $30.