I like Kelty Triptease myself but I spotted a viable alternative at another site:
http://www.backpackinglight.com/cgi-bin/backpackinglight/aircore_1_spectra_cord.html
Triptease holds a little better and doesn't slip like spectra cord.

Of course, a person could simply use the 7 inner strands from 5' section of 550 cord, that's easily the cheapest way to go since you already have plenty of 550 cord. (right?)