This was a nice racing frame, so if you're going to make it vintage correct, I'd go with 8 speed Ultegra or Dura Ace. Since they were legal, light, and fast back then, it was not uncommon to see it rolling on a pair of Spinergy Rev-X wheels, which you can get pretty cheap on ebay now. Other options for wheels would be Hed Jet, Zipp 440 tubulars (before the 404s), or a set of lightweight handbuilt wheels with low profile hoops. If you want a carbon fork, a Profile or Time fork of that era with a threaded steerer would look appropriate.

If you're going to use undated components, use whatever you want or whatever you get the best deals on. At that point, it's a tool and not a jewel, and it's not nostalgic enough for anyone to shed a tear over.

edit: Looking at other pictures of Klein Quantums, that looks to be about a 56.