Crab boil spice or shrimp boil spice can be substituted for pickling spice. Old Bay Seasoning can also be used in place of pickling spice.
Alternatively, pickling spice can be created from individual spices. It has one part each of celery seed and white peppercorns, two parts each of crushed chili peppers and bay leaf, and four parts each of mustard seed, dill seed and coriander seed. An example mixture using these proportions is 2 tablespoons of celery seed, 2 tablespoons of white peppercorns, 1/4 cup of chili peppers, 1/4 cup of bay leaves, 1/2 cup of mustard seed, 1/2 cup of dill seed, and 1/2 cup of coriander seed.