Where can you buy cartridges for a Hercules 38 special gas pen gun?

Anyone that reloads ammo can reload a 38 caliber pen gas cartridge using any spent 38 caliber cartridge. Just use the primer and no powder. Inside the cartridge a small amount of cotton is placed first, then the irritant (cinnamon, cayenne or other fine pepper) is placed in. Again a small amount of cotton is put on top and the cartridge is sealed with wax. When discharged within 5' -10' at an assailant it will temporarily disorient the person giving you the opportunity to relocate. Much better than killing someone.