That is one of Pierce's fonts, it is actually their most commonly used one. Like letterman7 said it is not available for purchase. RJ Marx in Wisconsin used to typeset it for a fee but I heard they don't do that anymore. I have my own version that I made to match it, you can start with something like Beaufort, OLSignpainter, Copperplate, ITC Symbol etc. etc. and just adjust it to match.