On my boat, I have an eyestrap that fits at the location where there used to be a horn cleat for the outhaul a few inches from the end of the boom. Initially, I tied my reefline to it. However, it got damaged at one point, and not being able to secure a matching one, I replaced it with an eyestrap, reusing the holes. Because of that I have it set up at 90° to the direction of pull, which is not advantageous. I've used the reef (and have the photo to prove it) but the arrangement so far appears strong enough. It's not using rivets, but I don't remember whether the holes were tapped.

I'm not sure what the maximal expected loads are. The usual way to estimate these is to figure the sail force required to capsize a boat with fully hiked crew.

(from:

https://forum.daysailer.org/forum/viewtopic.php?p=36850#p36850)

The 3' estimate of the lever arm in the diagram is perhaps a bit small, let's say a crew can hike to get an effective lever of 4' (and the reefed sail sits lower, so 8'). Those lever arms are nearly 1:2, so the maximum heeling force is around half the weight of boat and crew, or 5-600#.

The total sail force translates into luff tension, leech tension, outhaul tension, that have some component along those three lines and some component in the direction of heeling. That part gets a contribution from where the luff is in the sail track. The induced leech tension should be greater than the heeling force, because it's the addition of the two components, one inline and one across. But the leech is only one of three edges tensioned. I think, in the end, the effects probably cancel approximately, so that we get a few hundred pounds of effective load on that eyestrap.