There is absolutely no reason why there should not be access where any person can run a firearm SN or vehicle VIN and be able to determine if it is stolen or not.
The feral Govt acts like this is 1965.
A lot of incompetence and malfeasance on the part of government agents would be revealed if that was publicly and freely available.
That said, for the past twenty years, I’ve always been able to call the local PD non emergency numbers when purchasing a car and every department was happy to confirm make, model, year and whether it was stolen.