Sony have announced that, sometime in the future - probably the near future - they'll be releasing a Warhawk-themed value pack over the PSN. Said pack will roll both Warhawk expansions (Omega Dawn and Operation Broken Mirror) into the single release. As of now there's only British pricing available: the pack will go for £4.99, a charitable offering when you consider they each went for £3.99 when first released. North American pricing can't be too far away.
Warhawk DLC bundle incoming [CVG]