When I've been to CT islands I've seen no difference in what is offered between own region and international.
Not sure what you mean by official list, I've checked Liquefy's walkthrough faq on gamefaqs for the CT exclusives and they are:
Bottled Ship, Box of Chocolates, Sand Castle, Sea Globe, Ukulele, Whirlpool Bath, Muumuu, Hibiscus Hairpin, Blue Wet Suit, Red Wet Suit, Striped Wet Suit, White Wet Suit.
So the pink wet suit is available via your own island, while Muumuu & hibiscus hairpin are only on CT.
What I found tho is that the rarer items - like the pink wet suit I was able to pick up on a CT island, while my own island seem to just get the same old, time after time.
On CT islands you don't get the CT membership form, another item in its stead.
You can get rid of that membership form on your own island if you have 4 characters and they all get the CT membership (needs confirmation, haven't done it myself) or take a visitor (from another town) over to your island - that gets you an extra item in the shop rather than the membership form. (again, confirmation, its ages since I took a visitor over).