Nowhere near you, but if you can find another tourist with longer spokes that they can spare, you can use the 'z-bend' trick, cut off the head so the remaining spoke is a bit longer than your original, and then put the bend in to create another head to get a resulting spoke of the right length. You can see pictures on this thread about 3/4 of the way down the page:
http://www.bikeforums.net/showthread.php?t=239070
I've done that before and its worked perfectly for me, drive and non drive sides in the rear, and I didn't need to remove the cassette to get one in on the drive side.
Enjoy the tour, and hope this helps.