I got my chest rig yesterday, and I really like it, but I was sad to find that my Source 3L bladder is too big to fit in the pouch for the hydration bladder. I know Camelbak has some 70 and 50 ounce pouches, specifically these:

http://www.camelbak.com/government-military/accessories/omega-waterbeastreservoir-70oz.aspx

http://www.camelbak.com/government-military/accessories/omega-waterbeastreservoir-50oz.aspx

I'm guessing the 50 ounce should fit, but I'd like to be able to use the 70 if it will work. Does anyone have any idea if the 70 will fit, or a recommendation for a different bladder that they know will fit?

My CamelBak Omega 3L fits perfect. I did a quick search on the dimensions of the Source 3L and couldn't find them but you may want to compare...

Omega 3L Reservoir Dimensions:
Length IN (mm): 18.11 (460)
Width IN (mm): 7.87 (20)
Depth IN (mm): 2.95 (75)
Weight EMPTY LB (KG): .62 (.285)
Weight FULL LB (KG): 7.27 (3.3)

Awesome! Thank you.