This year in Melbourne at least, the BSF are everywhere. They are attracted to my worm bins which is used for general food waste, and there are always BSF larvae in it, and flies in the vicinity. I like it a lot, as they break down the kitchen scraps in a small fraction of the time that the worms take. I couldn't be bothered doing anything with the larvae (seeing how it is just a worm bin and picking them out would not be fun), as long as they eat the scraps.
There must be someone in your locale that would be happy for you to catch some of the flies or could spare some larvae? I don't think they would do so good in the post. Aussie Post might not like it either.
