Ask for three mm, 7×19 stainless wire. Good hard eye at sail end and a soft eye at the lever end about four inches long.
Rope tail, four mm, pre stretch, three strand so as to make a nice rope eye through the wire soft eye.
Over buy the rope tail,it gets worn fast, so can be respliced at the good end and chopped off at the bad.
Wire does stretch some from new so do not be surprised if the rig goes soft,just reset the tension again.
C P 🙂