Yes, that plastic accoutrement is probably the clam cleat that would be used to tighten the leech line. Now look for a narrow pocket straight up the leech from that plastic cleat -- the line goes inside that. Perhaps you can rig another one yourself. Use something like an electrician's fish tape for the job. Use some small diameter line for it, and make sure it fits properly into the clam cleat before you go to the trouble of running it. I'm not sure how the line is terminated at the head of the sail, so perhaps someone else can answer that one?
Or -- take it to a sailmaker to have one added. As you are discovering, it is a useful sail control.
SailorMitchSailing winged keels since 1989.
1.20.09 Bush's last day the end of an error !! Hopefully we still have a constitution and economy left by then.
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