Discovered Paracord Planet has 1/16th inch black elasticized cord suitable for rail lines and wide choice of cordage (colors/diameters) for standing rigging. All at reasonable prices / various lengths and quick delivery. New to this site so info may be already known.
Art

This is helpful. I just joined this forum yesterday hoping to get this kind of info. I'm getting my Nirvana II boat back in the water after several years of non-use. The In/Out line to the jib sheet got broken and I've just spliced it temporarily.

JoAnn's Fabrics is also a good place. Looks more like real rope.

Thanks. I may need to take my old line to a local store to make a proper selection. I'm unsure how to specify or select correctly from an online source. Is it thread, twine, or ? Which material and "gauge", etc.

Mine is thread. Don't know what gauge but it is pretty thick. I took a sample of the thread that came with the kit with me to JoAnn's.