I've been searching for a 1/18 model of the 03 Le Mans winning Prodrive Ferrari 550 for some time now, and I finally found one. And they make tons of different liveries for the car as well!
The only downsides is that the model is a kit, so you have to build it, and it's kind of expensive, at €180! It sucks because I've never had the patience to build models well, I always just throw them together, and they turn out like crap. Hopefully I could find someone very good at model making and pay them to make it for me because I suck at making models, haha.
18 MGMODEL