G550
If you have your contract and all documents in order as well as signed expense sheets you do have recourse and this can be filed under the civil case section of courts. They will be served a notice in 30 days and have to respond. It is a different matter how long it takes to resolve and the cost benefit analysis especially if you live outside India.
A suggestion would be if you can file the complaint in your home country (possible if the contract was signed by you there) and then get some sort of order passed which would jeopordize their travels to that country. Usually Singapore and / UK are good places to sign and register contracts with Indian companies.
Note: Not an attorney but have seen this done in the business I am in and use this frequently when dealing with countries of the commonwealth.
