On the Krylon website the only primer I saw that even came close was ruddy brown.
Also, it was my understanding that red oxide is a type of primer, not just a color. Regular primers are porous in nature and will allow moisture to penetrate... which equals rust down the road, wheras red oxide is a kind of primer that is not porous, ie, it does not need to be topcoated. I may be mistaken. I only bring this up because a lot of effort may be taken to clean and detail something to look correct or close to correct, and by picking a product based on color alone you may end up making more work for yourself down the road.
I would go with Rustoleum instead of Krylon with that in mind.