1. The problem is to find the missing number in the subtraction equation $$\_ - 514 = 253$$. 2. We use the subtraction property: If $$a - b = c$$, then $$a = b + c$$. 3. Substitute the known values: $$a = 514 + 253$$. 4. Calculate the sum: $$514 + 253 = 767$$. 5. Therefore, the missing number is $$\boxed{767}$$.