It wont be a problem as the restaurants dont usually put the menus up until a few days before and you can book right up until the 31st. it depends on what you want, but they usually cost from R1750 for a set meal of 4 or 5 courses. Some include a firework display at midnight which is lovely. The hotels start taking reservations approx a week before. It depends on the hotel, but will probably cost from R3500 per person uncluding dinner, entertainment and firework display The New Year is welcomed in by almost everybody in Mauritius and the 1st and 2nd are public holidays..