Yeah, just paint them if you can't find them advertised anywhere. I figure dealers don't get too much of a break on a wheelset so cheap. may have something to do with the customer service since you aren't spending $3g's on a baller set of chrome DuBz, y0! lol.
I wonder about the back glass. In my wagon, I had shattered a long piece of rear side glass (volvo 850 wagon). Because of the size of the glass, I thought it would be kinda heavy, and thought about replacing it with polycarbonate or something. But when my buddy and I pulled replacement glass at the junkyard, we were shocked to see how light it was - only a couple pounds. I immediately realized it wasn't going to be worth the effort to switch to poly/plexi/lexan. I'd save more weight by vacuuming the interior. lol.
I parked next to a black MP5 last week - I noticed it didn't have rails or crossbars. I got out of my car and looked down on the roof, and saw the 4 little plastic fillers...I was tempted for a second to pop them off. haha!

Nah, I don't think the crossbars are really that much of a detriment to the airflow. I've got a sunroof baffle up there too, which seems like it may act as a fairing to a certain extent. Plus, I'm paranoid that right after I remove the rails and crossbars, I'll need to use the roof rack for something. It's typical of my luck!
On a side note...I got
31.98 mpg average for this last tank of gas! Still NO aero mods at all (car is 100% stock save for a cone filter). Car also had a minimum of 100 lbs of cargo at all times. I think I can hit 35mpg average with the stock gearing and no weight redux. My daily drive is about 17 miles each way of mostly highway (maybe a dozen stoplights max), and then a 60-mile each way, all freeway commute a couple times a week. My speed is typically CC set for ~65, with occasional coasting on downhills and speeding up to go around idiots who still can't grasp the concepts of merging or lane changing...