Well, if going to Asia or the Indian Ocean destinations, you're roughly talking about 11 days in-country.

One other option to consider is Thailand. July should not yet be the rainy season in some parts of the country (you'd want to check the aforementioned monthly climate sites for that). And it has: a fascinating culture, good infrastructure for getting around, friendly people, nice beaches, great and cheap food, far less expensive than some other destinations, and really great value in terms of the hotels, particularly during an off season like July. That is, a hotel that might cost you $500/night in Europe or the US might be $200/night in Thailand.

You could combine a few nights in Bangkok with the rest at a nice beach. And even at the beach, you could tour around the surrounding area in various ways.