Welcome dude! What kind of sound are you looking for? Tubes and speakers all work together to get you to that "sweet spot". Here's a good site to start with as far as the tubes go:
http://thetubestore.com/
Maybe Monster can help you with the speaker selection, he builds amps. As far as servicing just shoot on over to the Laney site, they should have a link for servicing with a list for international service centers. Good luck man.