Nw I have no idea whom made this sling but it has the correct period fittings to go with my Rigby Mannlicher so when I saw it hanging up in an old gunshop that was closign down I brought it:-

And finally on the rifle:-

I keep my eyes open at shows etc but have yet to come across another one. There is also the snap hook as used by Parker-hale on their target slings. Sorry no photo to hand right now.