Hello Jim and thanks for responding. Sorry, I was away from the Forum for a bit. Apparently, there were two types of boarding pike heads used during the American Revolution by the colonists. One was indeed the one you mention, the long 'spike' type with 4 sided blade. But just as popular for whatever reason was the leaf pattern, as this one I posted. Neumann shows several very distinct patterns of these in 'Swords & Blades of the American Revolution.' By the time of the War of 1812, the leaf patterns had become quite elongated and now a shorter 4-sided spike head was introduced. This latter pattern would basically remain the type seen after the Federalist Period until the eventual removal of the pike from ship's armament stores at the end of the 19th c.
Good idea about the artwork of the period as well. I'll have to keep an eye out!