Perform the indicated operation. Write the resulting polynomial in standard form and indicate its degree.

To perform the operation \( (8x^2 + 7x - 1) - (2x^2 - 5x) - (-5x^3 - 4x^2 + 3) \), we will first distribute the negative signs and then combine like terms.

Step 1: Rewrite the expression with distributed negative signs:

\[
(8x^2 + 7x - 1) - (2x^2 - 5x) + (5x^3 + 4x^2 - 3)
\]

Step 2: Combine like terms:

Let's group the terms by degree:

- For \(x^3\):
- \(5x^3\)

- For \(x^2\):
- \(8x^2 - 2x^2 + 4x^2 = (8 - 2 + 4)x^2 = 10x^2\)

- For \(x\):
- \(7x + 5x = 12x\)

- Constant terms:
- \(-1 + 3 = 2\)

Step 3: Combine everything together:

Putting it all together, we have:

\[
5x^3 + 10x^2 + 12x + 2
\]

Step 4: Identify the degree of the polynomial:

The degree of the polynomial is the highest degree of its terms, which is 3 (from the term \(5x^3\)).

Thus, the final answer in standard form is:

\[
\boxed{5x^3 + 10x^2 + 12x + 2}
\]

And its degree is:

\[
\boxed{3}
\]