Carbon fibre repair

I'd ask the UK Trek importers first. Apart from that, the only guys I know of who repair carbon frames are Calfee in the USA. I've seen photos, and the repairs are often virtually invisible.

http://www.calfeedesign.com/howtosendrepair.htm

I'm also wondering if you might be able to just cut it down and use a clamp and normal seatpost - but I have no idea what shape or diameter the seat tube is. Might be worth a try if the frame's otherwise a write-off.

http://www.carboncyclerepairs.co.uk/