Here's the correct url for your photo...
http://img142.imageshack.us/my.php?i...pview01hd6.jpg
It shouldn't be too hard to reshape that tube. Use a round file to take off the burrs from that nick on the left side. Then use a block of wood that's been rounded on the end to the same shape as the tube, then whack the low spots on the inside of the tube at about a 45 degree angle to bring them out a bit. The high spots will bend in on their own as the low spots come out. A little help from a correct sized seatpost or even a smaller one will help get the tube round again. Good luck!