The issue with shipping costs right now is EMS (and I assume SAL too) has been shut down due to the coronavirus issues. EMS (and SAL) relies on cargo space available on passenger airlines. With those flights almost non existent for the last few months, EMS packages stacked up to the point that Japan Post stopped accepting them. So right now you have to either ship items on a boat (takes FOR E VER, to quote The Sandlot) or use a dedicated cargo airline like FedEx or DHL (insanely expensive). Most of the popular online shops in Japan have updated their available shipping methods to reflect this current reality and thus you’re not likely to save much if anything by ordering direct from Japan. Once EMS (and especially SAL for smaller shipments) becomes available again, you should see a worthwhile savings ordering direct from Japan over a US retailer (even for just a single figure). Assuming the EMS (and SAL) pricing is similar to what it was before the pandemic, that is.
In case you don’t know what EMS or SAL are... EMS is JapanPost airmail. SAL is a cheaper option for smaller packages where the shipment is treated as surface mail in Japan and its destination country, but shipped as airmail when traveling between Japan and the destination country. Plain SAL is not recommended as there is no tracking and it takes forever (often 4 weeks or more). But there is a trackable form of SAL that’s still extremely cheap. It still usually takes around a month shipping time but it has a rudimentary form of tracking (it’s not real time but rather updates well after each checkpoint) that at least allows you to tell if the package got lost or not.