The slings I use on my Ruger #1 and BRNO 602 are from Trader Keith's. He advertises in GunList. They are nice-looking and well-made, and use brass & leather for attachments to the swivels. The sling itself has two "rubbery" strips running along one side. These strips impede the sling from slipping around on your shoulder.

I find these slings really dress up my rifles, adding that "British big-game rifle" look.