My new 5-yard wool kilt from J. Higgins fails the stretch test.

I knew it would because Higgins does not add stabilizers to 5-yard kilts. The stretch isn't permanent (yet). It is noticeable when worn (wavy dark vertical line) but looks fine when hung up / laid out.

My questions are:
  1. Is it possible to add a stabilizer to an unlined 5-yard kilt?
  2. Is is cost effective to do so, versus saving up for a properly-made 8-yard kilt?