In the past I have bought 2 OD/Black camelbak hydration carriers. Both of them were second hand, used. So I never got to use them as I didn't think it was hygienic.
I had been looking around for some cheap replacement bladder and in the end I found this newer edition OD/Black camelbak hydration carrier which uses the same bladder. The best thing is that it was so cheap. It cost me just half of what they charge for a new bladder!
Anyway here's the pic of the new carrier and the old carrier (with the new bladder in it).
Both the new and old carrier have an NSN tag. The NSN tag on the new carrier (left) is visible through the filling hole and the NSN tag on hte old carrier is sewn on one of the shoulder straps.
Another reason I bought it, is because I can use it for my FSBE loadout. Check out the upper and lower reference pictures!