I've seen many with the 1907 sling.  Personalty I like the Trap door, or 1873? sling or a Mills tropical sling.  I would say a Kerr Nubuckle is also appropriate.

Original slings are great for display but for range, I want new leather.  I have seen old leather fail causing damage to the rifle.  You can get a repro 1873 for $25 and it's well made with original style marking.  The repro Mills and Kerrs I have are nice enough for range work.