This date has so much going for it. The mintage is super low (30 Proofs, with fewer than that known). It's a great date from deep in the Civil War. Plus, Proofs from thus year are usually well-made, often with great Cameos.
It is highly likely that all Proof 1863 Half Eagles are Cameos. However, the existence of non-Cameo Proofs in the PCGS Population Report seems confusing. In the early days, PCGS did not recognize Cameos and Deep Cameos on gold coins and were the coins resubmitted today, the numbers in the population report would shift towards the Cameos and Deep Cameos.
The finest example is a PCGS PR65+DCAM that currently resides in the Simpson Collection.