This seems to come up once or twice a year. I'm no expert, but from what others have posted here on SB, the short answer is that you can't have it commercially filled on this side of the ocean. Certification starts at the design and manufacturing stage, so you can't add it after the fact. Testing and the stamp that goes with it just says it still meets the original certification.
A specialist hydro testing shop in a major seaport used to dealing with foreign vessels may be able to test it for you, but most local hydro shops probably won't know how to deal with this, and it still won't let you get them filled by someone else, although some people with their own compressors apparently find it acceptable to fill their own non-DOT/CTC certified tanks as long as they've been recently tested, for which it doesn't sound like there is any legal restriction as long as they are purely for your own use.
Now if you're just looking to get it inspected (VIP), anyone knowledgeable should be able to do it. But you still won't be able to get it filled.
But the simple answer is to wait until you can ship it back and use it over there.
