You can either flash the stock recovery file by itself or just flash the complete stock ROM. You'll find the stock recovery image file inside the stock ROM zip file. Let me see if I can find this for you. You can find your Micromax Q300 stock ROM (Android 5.1 Lollipop) from here: https://consumingtech.com/download-micromax-firmware/
Hi Arya. Are you pertaining to a stock rom? If so, I suggest contacting Micromax about it cause I can't confirm if any of the Micromax Q300 stock that you can download online is a legit one.