IMHO "crew cards" are worth very little.
The best "crew card" is a cheap pilot uniform with the maximum amount of gold on the shoulders. It gets you respect everywhere you go - especially in the "3rd world of aviation" (south of the Alps, basically
). The stories I hear regularly about stunts which pilots thus dressed have done are just amazing.
And you need only one duty-free ("commercial") fillup to pay for the cheap uniform.
Just don't turn up where anybody will recognise you
