Iíve got an unopened/unused pack of self-tensioning lines from Jacks R Better (http://www.jacksrbetter.com/shop/self-tensioning-lines/). It comes with a set of two. They run $9.95 plus shipping.
Iíll sell them to you for $8.00 which includes shipping anywhere in the U.S. by snail mail. Paypal only.
First to PM me gets Ďem.