depends on which jobsworth you get on the day
Probably best if you can get an end to end - eg Perth LHR from a place they know about mines (ie NOT the UK)
The question is also are these business samples or souvenirs" - in the first case ship them by a specialist carrier and charge the company. In the latter stick them in the post surface mail
Once managed to talk my way through Sheremetyevo with a few rolls of metal magnets but it took some doing (and the gift of some to the security team)