Take the broken recoil starter cord compleatly out of the T handel, you might need a small screwdriver to remove a plastic cap to get at it, then try to unknot it to get an idea of the origernal cord thickness, usually measured in MM, places like B&Q, the Range & other craft places sell it, shop arounnd.
You might find that you need to buy a full length of it, about £5.00 or so.
fully remove it all from the recoil spool, taking note of direction and how it wraps round, measure against the 2 removed lenths, in total.
cut a new piece, melt and smooth ends with wet fingers, then its just a case of installing it as it came off & making sure it fully recoiled, check gently before fully re-installing it, then test once its put back together.
Keep the rest as you might find it fits other items.
Mr L Croker, November 2009