Exporting Silver in low quantities

I have silver in a third world country. It’s certified. But in this country the the selling spread is huge. If you sell your silver and then buy it back the same day, between buy and selling spots, you lose 30%.

And another point is that, even the buy rate is below what I see as Oz silver market price.

So I wander if it’s worth to transport to the US, or somewhere where prices makes sense.

Has anyone had any sort of experience with this? Has anyone transported eg. 3kg of silver on a plane?