Seat Belt Bolt Needed

When I bought my 72 Dart it came with seat belts for the front lap belt not installed. I went down to hardware store got two grade 8 bolts that fit the body nuts. Passenger side worked fine, so wifey is safe, but drive won't line up. I beleive this is suppose to be a star head bolt which would allow this to line up through the outer hole. Where can I get one.

Thanks,