I looked in the ride store, WOD and even Villains n Vogue. None of them had the MR stuff which of course may change in the near future.
The MR are the only ones with any quality to it. I ordered both the ring and the key to help complete my Captain Jack costume. The key is perfect as is and the ring is about a size 8-1/2. Unfortunately due to the rather soft metal the ring is made of none of the jewelers will touch it for resizing. I had to cut the ring band and expanded it to resize it.
There are plastic versions that you can buy in the kids play set at any Wal-Mart but the quality is what you would expect from a kids toy. At only $15 each you are much better buying the MR stuff.
Now the compass (if you are interested) is another mater entirely. MR which has an unmatched reputation for high quality and accurate prop reproductions IMHO really missed the mark with the Jack Sparrow compass. From the pictures I have seen the compass looks brand new and would take some serious work to make look old like the one used in the movie. If you are using this for a costume the plastic compass you can buy at Wal-Mart would be a much more cost effective option.