You know that Janeway could have built her own defiant class ship if she really really wanted one.
Set up a base, piece together an industrial replicator, mine the shit out of an asteroid belt.
Hell if The Resistance in the Mirror Universe could make one while being hunted by the Alliance, at the very least, Janeway should have had a small fleet of Delta Fliers, at least 15 under her command, even if that would have made the show look too much like BSG.
Why don't they use their transporter to mine? They did that back in Archer's days in the Delphic expanse, didn't they? It should be much easier in Janeway's time.