micromatch 8 FOB header:
Consider buying another type of MEC switch with LED and simply replace the LED. E.g. 3FTH940, more expensive though.
Reichelt as found
Lots at Mouser but they have a center detent. You could remove the detent or leave as is! You get white LEDs in the Essential Kit to replace any LED colour.
You could try PTL30-15G0-502B2, this is 5k but should be alright (slightly different end slope!).
uSD card: no special requirement! No adapter needed! I’m using the 4GiB one from Reichelt.
Molex header housings:
Quite difficult to source at the moment, though Mouser claims they’ll restock in mid-January.
I think the following from Tayda should work, but no guarantees! Please test it!
You might like to also get the “wafer connectors” and crimp pins there too:
A-815, A-821, A-837