Not sure there really worth the effort Rocster. I thought they'ed be the cats ass for my AR Bushmaster I hunt yotties with, but I really didn't like the single point sling that much and found it uncomfortable and not as handy as I thought it would be. It may work for you, as I've heard some people say they like them, but I didn't that much. Might be fine for some things like tactical assults, but really how often do we do that on a daily basis?? For my uses, not worth the expense IMO.
I took mine off and gave it to one of my nephews so I can't get a measurement for you or I'd trace a templete of it and mail it off to you, I'm thinking it was about 1/16 or 1/8, with good steel they don't really need to be to thick to be able to hold a 10lb ,12lb rifle. And looks like it would be pretty damn easy to make your own, theres only one hole with a tab inside and a slot, pretty simple .