A sling for my MK5?

I need a good sling for my MK5, the reason why I ask this, is because my MK5 doesn't have two sling adapters. Not sure if you can see it on this picture, but it has this sort of adapter.



That isn't my gun. But that adapter is what it has.
If you can't see it correctly, heres the same picture.

http://www.airsoftgi.com/images/echomp5j6.jpg

What kind of sling can I use for it, thats sturdy and won't break on me? Anyone?