Since 2.3 I'm struggling to find these anywhere. I've done mission in boom systems all over the place and nothing. I had about 6 before 2.3 of which I have no idea how or where I got them. So that alone says to me there's an issue. If I can accumulate 6 cassualy playing before 2.3 then when I need them during 2.3 I can't find them, while actually looking for them. This is actually stopping me from playing the game how I want to, with the build I prefer. I think there should be more than one way to gain these elusive materials (high grade USS) or from elite npc's, the latter would be better because it would limit the amount of CMDRs below a certain rank getting them. Yours sincerely
CMDR PBSF LEXoMAK
CMDR PBSF LEXoMAK