I have 2 Butler Creek slings with sling swivels.  These are the stretchy slings they sell.  I also have 3 Vortex Spitfire 3x prism illuminated sights.  2 of them have American Defense Manufacturing QD mounts, and one is OEM from Vortex.  They carry a transferable, no questions asked, lifetime warranty from Vortex.  If anything happens to it, send it in and rest assured it will be fixed or replaced.  Check out Vortex's site for specs. 

Slings - $20 each

Vortex Spitfire OEM mount - SOLD

Vortex Spitfire ADM mount - $200 each