In 1867, the U.S. Mint sold 625 Proof Indian Head Cents at a premium to collectors and, presumably, a few dealers. Today, the majority of the original mintage still survives, as evidenced by the PCGS Population Report, which shows forty percent of the mintage in a variety of grades and colors. This does not count the hundreds of raw coins that are either ungradable or have not yet come through the grading services. Of those that are certified, the majority are Red & Brown. Red examples are the next most plentiful, followed by Brown examples, then Cameo examples (which are understood to be Red). PCGS has not yet certified any Deep Cameo 1867 Cents. It is possible that some of the Red examples could shift over to the Cameo designation upon reexamination, as PCGS did not recognize Cameo Proofs in the early days.
Among the Cameo examples, the best are at the PR66CAM level.