Honestly, I don't believe they would. I know the question was only for curiosity, but...
If anything, they would have someone make it for them, specifically .
Why go thru the trouble of importing something watched when, people if that caliber, could make it, or have it made.
Any ideas we have would all be conjecture and none of our business.
And, honestly, if you have the skills to make it, and have someone who can distribute it, then you're already going to make 6-8x the cost, on a low-precursor-purchase, paying yourself for work, and selling it low-ball in bulk to someone.
Once ones skill improves, they could make it themselves, or will have found other ways of acquiring.
Catching a box or two is one thing, catching a metric ton of immediate precursor (about 5 barrels, give or take, at the weight of water) would be sketched, unless you got tons of different cargo coming a lot...