If you get the role of being the grenadier in your team, you might want to take a look at this holster for M203 shell grenades and grenade launcher which is available right now at EB Airsoft for US$43.55 with free shipping. You get to carry with you a dozen 40mm BB shower shells and carry a standalone grenade launcher too apart from your primary rifle and back-up pistol. For now, it's only available in black colour.