You could cut the cable from the one you have drill a hole through it that was the same diameter as the replacement cable ( random length) and silver solder the new cable into the existing brass barrel end. It would sure solve a lot of hunting around, and the cable would be secure too. Another option and one I used myself was from a Honda Rotary Lawnmower clutch cable, the inner cables are plastic or teflon coated and reduce friction considerable. I soldered the end on as described above.
Example: Not sure on the barrel diameter:
http://cgi.ebay.com/CLUTCH-CABLE-FOR...ayphotohosting