The word "tabla" can be very confusing to a new-comer to the genre. The Egyptians refer to the Darbuka-doumbek-derbekke-toumbeleke as a tabla because the arabic word for drum is tabla. It is also more commonly a word used to describe the pair of drums that is played in traditional Indian music.
What we know of as "belly dance"-Raqs Sharqi-Danse du Ventre is accompanied by the Middle-Eastern/ arabic style drums (doumbek, riqq, davul) and not the Indian "tabla" (although in this day and age almost anything can be used to play for belly dance including all sorts of electronics, drum kits and congas). The type of drum that you are looking for is the doumbek-darbuka.
A good darbuka will cost at least $100 and many that I own cost considerably more. They are available at almost any good music retailer, but there is a large discrepancy in quality from retailer to retailer, so most of us have learned the best places to buy. There are several tribes that specialize in talking about Middle Eastern percussion and music so I'd suggest that you ask around before you buy.
BTW I am a professional percussionist that plays for belly dance in the NY area.