Steve,
We cruise collector have to be crafty. It's the only way to stay afloat. If you sail into the convention with something few have you can chart a trade to get something that won't cost you a fortune and sink your ship. You probably think I'm all wet, but it's the line that works for me. I can ashore you that it is much harder to find missing cruise ship chips you need than other types of chips. Sometimes you have to take astern view and build a bridge before you embark on your quest for those missing gems in your collection. But now I drift from my main port, I mean point.
By the way, IS the water in the ship's toilets salt water?