Cobean's Battalion was from Adams County PA (after the War of 1812, Cobean erected a building on the square in Gettysburg, which passed into the hands of a man named Willis, who in turn was the host for Abraham Lincoln the night before the Gettysburg Address). The battalion is mentioned as a company in a late 19th century history of Adams County in the section on New Oxford, which is on the border of York and Adams Counties. There are only three names listed, all casualties (the wording suggests they were killed, but one may be a brother of my 3G grandmother; he lived to command a militia company during the Antietam Campaign).
You might want to go to archive.org and download The Citizen Soldiers at North Point and Fort McHenry. Cobean's Battalion is not among those for which a full roster is given, but it is mentioned in the report of one of the generals as serving in the entrenchments which were the fallback position after North Point.