Excuse my lame edit of your image in ms paint but this is what I was thinking. if it's to be CNC'd then it could easily be part of one programmed run.
The fixing screws is harder to advise on as they are not quite M3 holes in the card, or at least some high quality M3 bolts I have won't go through without wanting to cut a slight thread in the card hole. I used M2 for mine which are quite thin but allowed for slight inaccuracies in lining up all the holes. Maybe an M2.5 would be ok, (I'm not sure what imperial sizes it would corresponded to, I find it too confusing using fractions of inches :shrug: ) You will however have to be spot on with the hole positions and that is far easier said than done unless you could laser map them direct from the card into a CNC or something.