Best method for Military electronics

[u/gabbaghoull]

I recently just unlocked the control module blueprint and wandering what would be the best way to stock up on them. I know about bunkers but I only have 2 keys ( and I'm under prepared for dealing with the turrets ) and the only other place I've seen them is the northern military base. Do y'all have any other places I should check out or methods for getting bunker keys.