Scott: I think your "Rock Island - 1904" (48") sling is a model 1903 sling, for the early 1903 'Rod Bayonet' Springfield rifle, as well as, the Krag. This sling preceeded the model 1907 sling.

It is desirable and worth money, but, it appears someone has damaged it by cutting slots to create an extra hole for the 'button' and there may be a pair of extra holes for the 'frog - hooks'.

The other (66") sling appears to be a decent reproduction for the Trapdoor and Krag. The rivets and brass 'frog' give it away, as new manufacture.