We broke two or three of those on the Tornado when sailing with 200kgs crew weight (we also broke cleats and other stuff).

I think this little baby was what finally held together but things are getting a little fuzzy: http://www.harkenstore.com/uniface.urd/scpdinw1.ShowProd?409Z56LC3VXJE

Wouters suggestion is probably best if your halyard fits:
http://www.harkenstore.com/uniface.urd/scpdinw1.ShowProd?B4RPMEB9Y9AN94