Here are some of the options for you to choose from.
iBall Hybrid Dual: The device has hybrid support for USB 2.0 and MicroUSB and you can find most of the modern phones with OTG being supported. Though do note that type C connector based phones may not be supported as this one has different connector for MicroUSB 3.0 standard. The device write speed is of 15-18Mb/s.
Price : The device has cost of 496 Rs. (Amazon)
SanDisk Ultra This seems to be the perfect match of your requirement. It has OTG micro USB support. The writing speed of the device is above 15 MB as per your requirement. And the best part is it is backward compatible with USB 2.0 too. Which is not possible for most of the Micro USB devices in the market at this price. Suitable for both laptop and Android devices.
Price : It is priced at 436 Rs. (Amazon)
Kingston Digital 16 GB Data traveler : This is another model which is fit for your requirement. The write speed is also higher. The device supports the Micro USB OTG functionality. It has reversible type C connector. So this makes the price of the device higher than the other devices of same capacity.
Price : It is priced 2200 Rs. (Amazon)
Strontium Nitro Plus : This USB 3.0 device has support for OTG functionality. It also has the higher data Read 120MB/s and Write 90MB/s which is way above your specification. Supports most of the mobiles with USB3 connectors. Supports most of the mobiles with OTG support.
Price : It is priced at 452 Rs. (Amazon)
Verbatim Store 'N' Go Another interesting product with OTG support. It has high data read and write rate as per your specification. Being USB3.0 dual interface device with support for most of the devices, you'd find it handy to use. The device being plug and play, you don't have to worry about driver.
Price : It is priced at 825 Rs (Amazon).