Dear Ashish,
Many thanks for your mail - and you will enjoy making wine for yourself. Wine barrels thend to comme in two sizes - 225Litres and 228 Litre capacity. They are made from Oak, and their manufacture is a craft in itself, from very carefully selceted Oak, and fired with the greatest skills. Finding a barrel of the capacity you require will be exceptionally difficult - and you mat have more luck approaching people in the whiskey industry for such small barrels, although in Inida Commercial Whiskey Distilleries are unlikely to use Oas Cask of such small volume.
My recommendation is the following
Either
1. Up the volumes you wish to produce to the 225 Litre mark - this will be approx 300L Of Grape Must.You will then be able to approach most current wineries and buy a three year old barrel from them, or I can gladly put you in touch with some equipment suppliers in India who could help.
2. Use oak staves in a plastic container. Oak staves are planks of oak about 1m in length and only a few mm thick and possibly 10cm wide. A paket of staves has approx 50 planks and these will float in a container imparting oak flavour. Again you will have to make larger quantities than 25-30L
3. Contact Whiskey Distilleries for smaller Oak Casks (Ensure these barrels are sterlised with antibacterial agents - preferably with Sulphur Dioxide also.
Let me know if this helps and you wish to pursue any of the above options
Puneet