I’m sure many do the same things as I do when looking for these but in case not..
1-Hifishark. Create a user, search for what you want, and click on save. It isn’t perfect, but works pretty well monitoring many of the sites that sell used audio gear
2-ebay-create a notification when someone lists them. You can also see where they are shipping from and sometimes see them listed on Craigslist if the seller is nearby or are willing to ship. I did this on a couple of pairs
3-The site Reverb is a good source. I purchased a pair there as well as some JBL 708i speakers
4-AVSForum Classifies-Found a pair of 6332 being sold there. The ad was pretty old but he still had them with original boxes and perfect condition.
@concorde1, the original boxes and packaging are pretty stout and I would think would ship ok internationally I would think. If someone doesn’t have the original shipping containers if they put them in bags, then tape cardboard to the front baffle, it protects the drivers really well (tweeter is recessed).
Good luck in your quest.