I'm the new owner of a 1879 Trapdoor mfg in 1885 (2704xx). I've been researching my text and it looks like a correct sling would be a cut single hook? This model or variation would predate the early double hook, correct? I can find quite a few double 1887 double hooks but very, very few single hooks. Anybody know of a source for an original correct sling for my rifle? Would a cut single hook be correct for a 1868 trapdoor as well?