The original statement as to not being able to replace them was silly, given federation tech. Really they should have at some point just had some throwaway line about having converted some facility to photorp production.

This argument always annoys me.

Of course they couldn't replace them IN THAT MOMENT, but they clearly made upgrades and changes to the ship as they traveled.

If they built an astormetrics lab, hydroponics bay, and a borg-enhanced runabout, then they could figure out how to build torpedoes.

We also see them at least once bartering for weapons and experimenting with new forms of warp travel and energy collection.

I'm sick of the torpedoes thing. We're grown-ups. We dont need a throw away line for every little thing that changes between day 1 and day 2k+