Your “up close and personal” photos make this a little like the blind men and the elephant. Each part tells us something, but the whole is difficult to understand. Is the M a sailmaker’s logo or a class insignia? Where is the C 99 positioned? Which edges of the sail are we looking at, the luff or the foot?
It is strange to see a sail slide and what looks like a sail slug on the same sail. The slug also looks like it is mounted sideways, and is not symmetrical, so perhaps it was added later and isn’t supposed to function as a slide at all, but as an attachment point for something, perhaps like a Cunningham. Without seeing the whole, it is all just shooting in the dark. Based on the amount of corrosion on the grommets and the fact that you don’t have the spars, it would appear that this sail might be really good for raking leaves or catching paint drips.
