You can place a counter order of Buy Limit at ₹730 (As per your example). The margin required will be displayed while placing the counter order but an additional margin will not be blocked for such an order.
Let me give you an example by placing an order along with some screenshots for more clarity.
1. I'd shorted 6 Qty of SBIN at Market (₹428.40) in Intraday. The margin required is around ₹385 for placing the order.
2. I've placed a Buy Limit order at ₹425 as displayed in the image below:
3. As you can see in the image below the utilized amount is still ₹385.56 and no amount is blocked additionally for the counter order.
Hope this clarifies!