The only way to increase the damage of your fighters is 1) getting higher quality fighters (through the dilithium store or romulan rep) or 2) using skills that increase all damage done to a target (like attack pattern beta). There aren't any consoles that boost fighter damage, c-store or otherwise.
There is one other option, though: Use Flight Deck Duty officers. There is a version that increases damage of your fighters while they are on escort duty. There are also others, with nice features, check them out.