Here are my suggestions:
Contact the Venango County Historical Society:
http://venango.pa-roots.com/venangohistoricalsociety.html(The Pennsylvania Grade Crude Oil Association was headquartered in Oil City in Venango Co.)
They should be able to point you in the right direction.
Or you could take a chance and call the Pennsylvania State Archives:
http://www.portal.state.pa.us/portal/server.pt/community/state_archives/2887Ultimately, the question is whether the association's papers were donated to an archiving organization after it folded (it appears to have ceased operation in the 60s). That's probably the only way you'll get a comprehensive list.
The Pennsylvania Sec. of State's office has info about the Association, but it can't be pulled up on their website. It was apparently incorporated in 1924 and then reorganized in '53.