This model has been around since at least 1960. Thus Col. Killian could have used it to go forward to at least the year 2001 and pick up a laptop computer with Windows XP and Word and an HP Laser printer and return back to 1972 to complete these memos.
So obviously the documents could be authentic.
As a matter of fact, I think I saw someone fitting Killian's description in Comp USA last week buying a lap top. Coincidence? I don't think so.