Gew 88 with unusual sling

Happened across an 1895 Spandau Gew 88 today, 'S' marked only. Not a Turk example.
It sports an unusual sling that appears to have been with it for quite a while..even has conformed to the shape of the rifle. Just a single strap of leather, no means of adjusting it.
Receiver siderail is marked 'NM', 'new material, I believe.
Bolt is not matching to the rifle, but it is not far off. Rifle is numbered 7881 with an 'a' suffix, bolt is 7987 with a 'q'(?) suffix.
It has a regimental marking which, as far as I can figure, is the 12th rifle issued to the 8th company of the 100th Infantry Regiment..(if I am incorrect, please chime in)
Just got in with this one, haven't had a chance to get inside it yet. Would be interested to hear if anyone has seen a sling like this one on one of these.

Looks the same as on mine:thup:

Your rifle looks to be one of the south American imports . The sling would be typical for that . The bolt is over 150,000 off minimum .