63 dodge dart drive door rattles

that's not a simple answer--- post some pictures of your door & seals up.
Do you have a 63 manual? it has adjustment procedures for the door.
Most likely new door weather strip would help -- then re-adjust the door mechanical s & you should be good. As long as nothing is totally wore out.

how bad are your seals now?
is your striker contact loose?(possibly moved from use)
A little time & that door will shut as good as new, Lawrence