Have you tried the fishermans mission? They may not be exactly what you're looking for but they should probably have information on other groups who could help.
Fishermen's Mission Head Office
Mather house, 4400 Parkway,
Solent Business Park,
Fareham,
Hampshire PO15 7FJ
Telephone: 01489 566 910
e-mail: [email protected]
You do not mention whether they are Merchant Navy or Royal Navy. You could try Shipwrecked Fishermen and Mariners,
Royal Benevolent Society
Dept, FULL
1 North Pallant
Chichester
PO19 1TL
01243 789329
Good Luck, Ex MN.