Big Bad Toy Store has a lot of Vintage toys, but often they are not complete (or at at least not complete in your sense of all paperwork)

http://www.bigbadtoystore.com/bbts/p...ge&list=recent

Online stores like Robot Kingdom also have old G1 toys.

Pretty much everything between 1987 to 1991 has not been reissued, although there are some exceptions.