There is quite a large variety of Kosher food products to be found in local supermarkets, being that a large selection of major US brand foods are Kosher by default and are the majority of food products in Grand Cayman are imported from the States.
Foster's Food Fair, Kirk Market and Hurley's are some of the main shops in Grand Cayman, they all carry hundred's of Kosher products. Cost U Less is a discount wholesaler (similar to Costco) where you can purchase Kosher Fish and other products in bulk.
Foster's at the Strand (in the heart of Seven Mile Beach) carries Glatt Kosher Cold Cuts, Hot Dogs, Ground Beef, and Empire Chicken, along with lots of other Kosher staples.
Other kosher products are available at the large supermarkets, but most likely will not be Cholov Yisroel, Pas Yisroel or Bishul Yisroel.
The Tasting Room located at the Caribbean Plaza carries some fine Kosher Wines.
Chabad Cayman makes a bi-monthly Kosher order from Miami and you can request some items not readily available on the island.
Please be advised that food items generally cost up to a third more expensive than in the States. Due to the nature of the island, many food items are seasonal and can not consistently be found in local groceries.
Ready Made Meals
The Ritz-Carlton Grand Cayman carry's Kosher Meals from Sterling Kosher Caterer's in Miami (under Hashgacha of the OK)
These meals can be ordered by hotel Guests or to dine in at the Ritz Carlton, orders should be made directly from the hotel.
The Westin carry's Frozen "Airline" style meals.
They are pre-made and frozen and you must select from the Menu selection of what is in stock.
Cayman Customs regulations
Small quantities of Kosher meats (up to 25lbs) may be brought in by passengers in their luggage as long as the meat is from an approved country and it is for personal consumption only.
It should be pre-wrapped under a brand name and have the Official Seal of Inspection of the country's Meat Inspection Authority.
All types of approved meats are allowed from the USA, Canada, CARICOM States, Australia and New Zealand.
No fruit or vegetables can be imported into the Cayman Islands.