I have heard if a merchant is dead, their inventory (or at least the portion that came from GRA) will migrate to the Gun Runners. Is this true? I have killed the Van Graffs and it has been over 6 in game days with no sign of the Sprtel or the Smitty Special. If it does migrate, how long does it take?

Yes, I believe that is true, I killed the Van Graffs a long time ago and when I loaded GRA the smitty special and sprtel were both for sale at Gun Runners,

^this. Does the guy from the legion fort sell anything unique? how about the guy from the strip, cause he wont sell me [censored] since I am idolized.