Buy shimano 10sp bar end shifters and use the rest of the 7700 group along with the sram 10sp cassette. You can sell the used 7700 shifters for more than the retail cost of the 10sp bar ends- CX racers love 9sp DA stuff. The older rear derailleur will work perfectly with a 10sp shifter. The front derailleur's cage will be slightly wider than a 10sp one but it'll work ok.

ProBikeKit has the 10sp shifters on sale for $95.