I had thought Krugerrands would have been perfect as unique salvaged coins; and only available (in quantity) from old currency exchanges, and some safety deposits.
Of course, the new cities could have always http://i271.photobucket.com/albums/jj125/Gizmojunk/Commemorative-coin.gif.
Even http://i271.photobucket.com/albums/jj125/Gizmojunk/c846cdf52440e63a7e968d18976e2602_zpsuvp3jsug.jpg would work better than Bottle caps.
*It's nice to see you back.