Is it safe to assume that you're willing to fab new mounts for the coveted rack if necessary, or are you trying to find a rack whose mounting points are the same as the stock 84-87 rack, but is overall 2.75" longer?
What about simply tracking down a pair of inner tie rod ends which are (each) 1 3/8" longer?
...or for that matter... damn where did I see it... I could swear that I once saw something similar to a turnbuckle used in a tie rod. P'raps cut the shaft of an inner tie rod, thread the cut ends appropriately, and join them with a threaded sleeve?