Ummmmmm...that's a sail, not a sheet, modul8.
Matt, any decent double braid will work - StaSet is not bad. 7/16" would be a good size. If you go any smaller it can be hard on the hands. I order all my line from Layline, but you can find it cheaper elsewhere (particularly something as common as Sta Set). Google or Ebay will quickly locate it, I'm sure.
To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.