Awesome for Bass.
For a cheaper version try brown, Life Flex Wrap, furled to what ever length you need. Slinky, voluminous, and sexy. It has a bit too much volume for a true polychaete worm, a single strand with the end tied or superglued would give a right amount of "legs" to the pattern.
Comes in olive, black or brown and a few non worm/leech colours.
Just my 2 cents...I do love those articulating shank flies, but so much work