You could try getting a carfax report from the VIN number.
https://www.carfax.com/vehicle-history-reports/
That might give you some idea of dealership that the car has been through.
If you are lucky and it’s been sold at a dealers, they may still have some documentation for it (if you are really lucky).
It will also tell you if it’s been paid out as a stolen car and you have yourself a very nice track car.
Failing that, as Dan says, try calling Pennsylvania DMV and try the old ‘prior user lost the logbook but gave you a bill of sale’. You have since moved and want to get a logbook.
It might help if you have the history from the carfax to back up your claims and that bill of sale you have from when you bought it and imported it.