The other day I dug an unknown copper coin in an area that I have found coins as old as the 1840's. the coin is copper, quite thin and is just slightly smaller in diameter than a US quarter. on one side is 2 1/2 with a P above and a W below. The other side appears blank but it is quite crusty. The token has a slightly raised edge. I know this is a long shot, it is probably a token local to the area and may not have any known record of existence.
It was found on the other side of the state in Pleasant Hill Mo. Pleasant Hill has a lot of Civil War History. It was occupied by the Jayhawkers and burned, then later liberated by Quantrill and the Missouri Bushwackers.
Spence, that is an interesting idea. That would make perfect sense. I will weigh it when I get home. I showed it to a local historian. He told me there were a couple of businesses in town that this token may have come from. Pelzors Wagon & Woodworking Co. Circa 1870, Powell & Waylond Theatre Circa 1907. These are theories only, there is no known record of either business using trade tokens. Your idea might be a winner.