TnNuc-
Try Brownells. On page 261 of their latest catalog, they show their competitor sling, which is a copy of the 1907 military sling that's pretty standard for high power shooters. Hooks are order number 084-270-006. Keepers are 084-270-002 (tan) or 084-270-212 (black).
I recently read an article all about leather dressings and repair parts for slings, and if I come across the magazine, I'll be sure to add that info, too. It was recently on the racks, maybe browse a few magazine stands for Rifle Shooter or Guns or whatever I saw it in (dang memory is slipping faster and faster).
Sure hope this helps you out.
