I know I've given this idea before, but hey, I think it's a good one lol.
Get some glass candle jars for centerpieces. Fill the bottoms with sand or rocks and have a lit candle inside. It'll set such a romantic mood. And to fit in with your theme, get some camo ribbon and tie bows around the bottoms of the jars. I don't know how many tables will be at your reception, but I know walmart has this exact thing in their candle section. It comes with the glass vase, rocks and a white candle....all for $10. All you'd need is the ribbon.