The Javelin-Class Starfighter, a 500-Ton Multi-Role Fighter Craft w/ Missiles

[Arekonator]

Considering that you have less than eight days of deployment time, i doubt they will ever be far enough from the mothership for it to matter.  Maybe use two 25% size launchers and add magazine instead?

On somewhat related note, i would also cut out the engineering spaces out of the 250t one and tried to fit something more usefull. 

[Iranon]

Regarding reloadable launchers:

You need to make - and survive - 3 attack runs to break even with box launches. You need additional support capability (colliers or missile stockpiles).
This is before point defence, which greatly favours one sufficient strike over several small ones. Admittedly, the enemy may be more limited by number of salvos than number of missiles here.

Again, you insist on a marginal capability that may never become relevant, and reduce the efficacy for the simple and most likely scenario to a rather small fraction of what it could be. If you bring enough of an ammo train to support this, you may as well bring a dedicated strike fighter and only give the Javelin capability that can be had in a weight-efficient manner.