Yes the budget is enough. Save on money by going to supermarkets and pack your own lunch and breakfast. And some cafes can be cheap, just avoid the real touristic restaurants. For your nice dinner that you are going to have, I have some suggestions.
1. Located on a quiet street near the Eiffel Tower, Chez L'ami Jean has gut-bursting portions and authentic parisian dishes, they are worth your every penny. Their menu are made with seasonal ingredients such as crabs, oyster, fish to pigeons, beef and deer.
2. Le Bistrot Paul Bert
This bistro offers the classic French selections. They have fixed priced menus of 19Euros or 38Euros which consits of an appetizer, a main course, cheese or dessert for 19Euros. One recommended dish is the Paris-Brest Puff pastry that is stuffed with hazelnut cream. One tip is to make a reservation as early as possible as this place can be packed to the brim.
3. Vincent's Home Restaurant
Crazy about the French cuisine, Vincent allows you to sample wine from his large collection and which kind of food to pair with which type of wine. You will be able to discover the wine regions of France and other countries and be able to recognise wine without reading the labels.