Nobody can tell you that since it all depends on your particular situation. Your refund could range from $0 to over $1,000. That's just the way that taxes work. Nobody can confidently tell you that a loss of $X is going to result in a refund of $Y.
The IRS probably will be asking about the missing trades at some point, perhaps asking that you pay tax on the entire proceeds of the sale as they may very will not know that the sales were at a loss. If they do ask, you're going to have to amend anyway.