★★★★★
Where to Buy
★★★★★
Where to Buy
★★★★★
Where to Buy
★★★★★
First, BHT comes in different purities. The technical grades are intended for use as preservatives in gasoline, oils and biofuels. They can be 96-98% pure, which translates as 2-4% impurity. You do not want this grade of BHT.
What you want is food-grade BHT. Or better. The certificate of analysis will show a purity above 99%. So if the vendor does not state FCC (food chemical codex) or equivalent certification, either look at the purity numbers or don't buy it there.
In some countries, Customs agents have an agenda to prevent their citizens from accessing nutrients, pharmaceuticals and cures of which they disapprove. If you have a shipment of BHT that is seized and you cannot negotiate its release, consider a stealth approach. Order the BHT and have it shipped to a friend where it is OK, then have your friend repackage it in a birthday card, or a T-shirt, or a paperback book. Powder can be transferred from a bottle (bulky and conspicuous) into a plastic bag (or nested plastic bags with a layer of clean paper between to minimize sound and the possibility of a puncture). Capsules can be placed in a plastic bag, adjusted into a single layer, and the sir squeezed out to make a one-capsule-thick slab, which will fit in a Christmas card.
Your friend in another country can they send it to you as correspondence, or as a gift.
If you are going to dissolve the BHT in oil after you get it, for ingestion or for topical use, the BHT can be easily melted in a double boiler on a stove and cast in a mold as a bird, donut, candle, paper weight or other "innoccuous" or artistic shape.
Where there's a will, there's a way.
Good luck.