I grabbed 3 pairs of the last SB Jordan from a shop, no customs. It all depends on the shop. Perhaps it might be more paperwork for them when shipping if they claim over a certain value.
500 will take a perfect alignment of the stars imo.
you have to find your size, and a seller willing to part at that price... and all before someone else does.
500 vs 700 i know its 200 bucks but if you love the shoe and you're already willing to pay 500, just pay 700 and you probably won't...