Since the device is quite new, there are very little number of flip covers currently available for it. I could find a couple of them here -
1.SDO Luxury Mercury Diary Wallet Style Flip Cover Case for Xiaomi Redmi Note Prime
It is a mercury flip cover. Made from best quality TPU material, it can be bought in blue color variant. It also has a card and cash holder within the cover. You can buy it from Amazon India for Rs. 238.
2. nCase Flip Cover For Xioami Redmi Note Prime
Coming from one of the prominent names in cover and case manufacturers, this one has an inbuilt stand cover. You can get it in red color option. It is available on Amazon India at Rs. 285. You need to spend another Rs. 50 towards shipping charges.
3. Xiaomi Redmi Note Prime flipcover
It Is one of the premium cases available for your device. It is available in black color and can be bought from Amzer.co.in. The cover is priced at Rs. 649.