anyone know where i can get new gasket/door seals for my 91 ser?

Give these guys a try.
Tell them you are from the forum.
Courtesy Nissan (http://www.courtesyparts.com)

If you mean the ones on the inside of the door, attached to the car itself and not the door. That go from the kick panel all the way to the other side, Courtesy has those. They are ~$50 each.