You would think they test this stuff more thoroughly !
http://www.stuff.co.nz/travel/australia/6163633/Qantas-terror-blamed-on-computer
Anwar Bhai
This is an Hornets nest you stirred, 55 People Died due to non-authentic parts finding its way to an aircraft (http://en.wikipedia.org/wiki/Partnair_Flight_394) , investigators unearthed a big racket and people responsible are yet to be revealed let alone being punished, post this crash a lot of measures are in place as far as critical aircraft parts(Called 'Rotables') are concerned in the civil airlines, however the same is probably not true as far as 'use and throw' parts are concerned which are maintained 'On Condition', (something like our RC parts , we flog it till it breaks or gives up we seldom change them on flying hours) , the parts you mentioned are such parts (Also called 'Class - C Stores'), how far it is authentic is anybody's guess,
PS
Now you know why civil flying and i far away from each other ;)
PPS
Flight computer cannot overstress an aircraft, because in a Fly by wire system there are clipper circuits in place, which does not let the aircraft cross the structural limit, broken parts are to be within this limit, so if an aircraft is to be tested for 1.5 times its max yield nothing in the aircraft should break.
.....The FAA later found forged parts in larger operations; in particular Air Force One, the aircraft used by the President of the United States,