Websites like Carfax, vincheck, etc. will only work
with 1981 and newer model vehicles because that's
when VINs became standardized with 17
characters. Unfortunately since the vehicle was sold
in 1968, 55 years ago, it was probably scrapped long
ago. But if you really want to try to find the vehicle
you're going to have to do a lot of old fashioned
footwork. You will not get any help from the DMV
because of privacy laws. You should begin at the
beginning. Ask your Dad who he sold the car to. If
that person is still alive, try to contact them. If you're
successful, ask them what they did with the vehicle.
Did they sell it, trade it in, etc.? If it was traded in and
not sold privately the search is over. You'll never find
it. Typically Dealers keep records for maybe ten or
so years, especially from the days when everything
was done on paper. So I think the best option is like
traver91 said, get a similar vehicle for your Dad. I'm
sure he'll love it just as much, if not more, because it
came from you! Good luck with your search and I
hope that helps! Jim