They have front rotors for $58 and rears for $18. plus shipping of course, but still. The lookup I saw was for 2007 E350 super duty; not sure of what the interchange would be for anyone else's.

Brand name is "Ultra". I had a set of rear rotors from Ultra and I'm impressed. I completely endorse them. The anti-corrosion coating is amazing. I can share pics if anyone wants..