Hello
I have previously posted some information regarding St Lucia in the Tour Manager section of the Just You Community pages which you might find useful in preparing for your holiday. I have attached a link to the page here
https://forum.justyou.co.uk/thread-86313.html
As a rough guide (for budgeting purposes for an evening meal) in Eastern Caribbean Dollars
For local Creole type cuisine $55 EC - $75 EC (circa £15-£20)
For more expensive meals $90 EC - $110 EC. Although if you wanted to eat in the steakhouse in Rodney Bay this would be more expensive.
You need to remember that you will also need to add 10% Local Tax and 10% Service charge to the costs of the meal.
I hope you have a wonderful holiday in St Lucia, it really is a beautiful island.
Best wishes
Caroline