MickPC said.. Surf Eclipse on Ebay might be able to help. He replaced a middle AM2 centre for me for a very resonable price & Shapers are top blokes too.
I'm sure I could but your nearest futures retailer should be able to do the same. If you locals can't help I could get the futures dudes to send it straight to you rather than criss crossing the continent.
Just checked, futures do have them, tech flex fins cost $64.95 individually and could get them to you freight free for all 4. Send me a message if you want them. Ross