You cant beat Ireland on a good day!!! But it can be hard to find a good day for a chilled out sea trip!
Humm Ive been checking out some Kayaking trips to Vietnam http://www.easia-adventures.com/
No idea what these guys are like but they offer nice Packages. Im more looking for boat hire for 2 weeks.
Croatia has a stunning coast too and generally good water conditions.
Lots of Options In europe. I would say google is your friend.
Jim In Atlantic sea kayaking would be the man to get onto he leads plenty of Foreign trips. http://www.atlanticseakayaking.com/content/view/71/85/
On the Irish Front It could be a cool holiday to try sea kayak on all the coast lines in a week or 2 with lots of different providers. Weather might not be as warm but Hea you could be lucky!!