Igniters for visco are usually inert -just a length of fine resistance wire so less of a transport hazard. For less than 500 I'd still be looking at buying them within your country, while the cost per device will be cheaper from China, the carriage, and customs costs could make it cheaper to buy from a large scale importer. (in trade with China a 40ft container full isn't excessive and gets the best unit price).
This all started because I couldn't find a place cheaper than 40+ cents or more per igniter. Kinda ridiculous for a hobby. Someone just posted back to me in another fireworks forum that I am on, and it turns out that there is at least one supplier in th US that offers discounts on larger orders, and actually charges a penny cheaper than I could get it in China for a 1000 piece order. Actually it would cost me a little more because of shipping and taxes, but at that point the cost difference is in the noise. As it turns out, half the cost of the 1000 piece order from China is the shipping; this is true from all three suppliers that I got quotes from. The actual price per unit is only 14 cents, and that is what first caught my eye. So yes, if I were to place even a multi 1000 piece order, one would think that the shipping price would start getting offset. Anyway, for what good it is worth, I learned a lot today how this all works.